CHANGELOG.md

Changelog

All notable user-facing changes to Calibre-Web NextGen. Format follows Keep a Changelog.

Docker tags: :latest = newest stable release · :dev = every merge to main (canary channel — what the maintainers run at home) · :vX.Y.Z = immutable pins for rollback.

Compatibility promise: patch releases (vX.Y.Z → vX.Y.Z+1) are safe to auto-update — no breaking config, database, or API changes without a BREAKING callout at the top of the release notes.

Internal refactors, CI changes, and test-only work don't appear here — this file is for things you can see or feel when running the app.

[Unreleased]

Fixed

• Two people using the library at once no longer break each other's pages. The server kept one working copy of your library data and shared it across every request it was handling. As soon as any one page finished, it closed that copy, so any other page still being built lost the books it had already read and failed. In the log it showed up as Instance ... is not persistent within this Session, pointing at whatever the unlucky page happened to be doing at the time, which made it look like a different bug on every occurrence. It got likelier the busier the server was, so it hit big libraries, shared instances and anything running during an import hardest. Each request now keeps its own working copy (#1150).

• A page you are reading no longer breaks because a background job finished. Duplicate scans, thumbnail generation, metadata backups and Hardcover syncs all share the server's connection to your library, and when one of them finished it could close that connection while a page you had open was still reading from it. The page then failed, usually with Cannot operate on a closed database in the log. It was intermittent by nature — it only bit when the timing overlapped, which is why a manual scan could break browsing once and then work fine on the next try. Background jobs and page loads now keep their own handle on the library, so one finishing can no longer interrupt the other (#1121, reported downstream of #1048 by @auspex).

• Your library keeps working when its extra fields can't be read. Book pages, the books table and both search screens all ask the library for its custom-column definitions — the extra fields you can add to a book in Calibre. If that lookup failed because the library was mid-write, its folder had moved, or the definitions table wasn't there yet, those pages returned an error instead of simply leaving the extra fields out, even though the rest of the library was perfectly readable. Custom columns are supplementary, so these pages now load without them and note the reason in the log (#1153).

• A book that fails to convert now still lands in your library. If CWA could not convert an incoming book to your target format — a big or image-heavy PDF that ran out of time, a file with internals Calibre chokes on, a format needing a plugin you don't have — the book was dropped altogether: no entry in the library, and the file gone from the ingest folder. The log even said Successfully processed on its way past, so nothing suggested a book had gone missing until you noticed it wasn't there. A failed conversion says nothing about whether the file is a readable book, and the two settings that decline to convert — auto-convert switched off, or the format on your do-not-convert list — already import the original, so this was inconsistent as well as lossy. The original is now imported whenever a conversion fails.

  A long conversion needed a second fix to get there. Nothing inside the app limited how long a conversion could run; the only limit was the watchdog wrapped around the whole ingest step, and when that fired it killed the ingest outright, so none of the recovery above could happen — which is exactly what the reported 63MB PDF hit after 45 minutes. Conversions now have their own time limit set just inside the watchdog's, so running long ends as a normal failure and the book is imported in its original format instead of disappearing. Raising Ingest Timeout in CWA Settings raises both.

  Two smaller things from the same report. The log now names the folder it keeps the copy in, /config/processed_books/failed/, where before it said only "failed backup" — a copy existed, but not where. And when a conversion overran, the service claimed the app "should have timed out internally", which was misleading advice about a limit that did not exist; it now points at the setting that does control it. Reported by @auspex (#1094).

• Opening your library no longer runs the same search twice. Every visit to the library asked the server for the first page of books, then immediately asked for it again at a different size and threw the first answer away. Nothing looked wrong — the wasted answer never reached the screen — but on a large library that first page is the slowest query on it, and it was being run twice on every load, for every reader. The grid now waits until it knows how many columns it has before asking, so the page is fetched once (#1144).

[v4.1.21] - 2026-07-25

Added

• The reading-progress export now includes each book's identifiers, so an external tracker can match on ISBN instead of guessing from the title. GET /kosync/export previously handed out only title and author, which is ambiguous for reissues, translations and common titles, and left the receiving service to guess. Every exported book now carries an identifiers map holding whatever Calibre has for it (ISBN, Goodreads, Amazon, and any custom types), or an empty map when the book has none. Contributed by @Kyraminol (#1092).

Fixed

• Uploading a new cover now shows the new cover. Replacing a book's cover from the edit page appeared to do nothing — the image on the left kept showing the old one, so it looked like the upload had failed even though it had worked. The cover lives at a fixed address, so the browser kept serving the copy it already had. The preview now updates the moment the upload finishes. Reported by @chloeroform (#989).

• On a phone, the Edit button no longer sits on top of "Read now" on a book cover. The label was clipped to "Read no…" because the pencil overlapped its tail — 52 pixels of it, on both phone and tablet widths. Both controls are permanently visible on a touch screen, so this was what every phone user saw rather than a hover quirk. The label now keeps clear of the button at every width, and cards you can't edit still centre it as before. Reported by @Andrew-H2O (#1112).

• Search engines are now told not to index your library. robots.txt pointed at a file that had never existed, so every install answered "not found" — inherited from upstream Calibre-Web, where it is also missing. A crawler that gets no answer falls back to its own rules and indexes whatever it can reach, which on a server with guest browsing enabled is your catalogue, and by extension what the people using it read. The server now returns a policy that asks crawlers to stay out. If you deliberately want your library indexed, put your own robots.txt next to app.db in the config folder and it will be used instead — no rebuild, and it survives upgrades (#1104).

• Books you email with "Send to Reader" now sync your reading position. If you send books to your e-reader by email rather than downloading them, KOReader would push your progress and the server would quietly drop it — the position was saved but never attached to the book, so the library showed nothing and the log said No book found for checksum. The same book fetched over OPDS synced fine, which made it look like a device problem. The cause was on our side: the server recognises a book by fingerprinting the exact file it hands out, and it fingerprinted downloads but never the copy it emailed — which, with metadata embedding on, is a different file. Emailed books are now registered the same way downloads are, under both content and filename matching. Reported by @uschi1 (#627).

• The quick tag box on a book page now suggests tags you already use. Adding a tag from the book page offered no suggestions, so it was easy to type "sci-fi" once and "Sci-Fi" the next time and end up with two tags meaning the same thing — which is exactly what two people asked for after the full editor got suggestions and this field didn't. It now offers matching tags as you type, skips the ones the book already has, and still lets you type something new. Arrow keys move through the list, Enter picks, Escape closes. Reported by @magdalar (#741, #572).

• When KOReader says "Server push failed", the server now records why. Highlight sync gives the reader one message and no detail, and the server was writing nothing at all about it — a rejected push, a book it couldn't match, and a highlight it declined to store all left the log completely empty, so there was no way to tell them apart from the outside. Two of those cases even answered "success", which meant the reader reported the sync as fine while nothing had been saved. Every highlight sync now leaves a line naming the book and what happened to it — how many highlights were stored, deleted or dropped, and for a refusal, which field was wrong. Anyone chasing a highlight-sync problem can now get the answer from docker logs. Reported by @iroQuai (#920).

• Guests can open and read books again. On a server with anonymous browsing enabled, a visitor who clicked "Read" got an error page in the classic view and was bounced back to the home page in the new interface — no book, no explanation. Three separate faults stacked up on that one click: the classic reader crashed before it could render, the new interface mistook "this visitor is a guest" for "this visitor's session expired" and signed them out, and the reader then waited forever for personal settings a guest never has. All three are fixed, and a guest now reads with the default appearance while signed-in readers keep their saved theme, font and position. Reported by @bentsea (#1074).

• Author names in the reading-progress export no longer come out with a stray | where a comma belongs. An author stored in Calibre as "William H. Keith, Jr." was exported as "William H. Keith| Jr.", because Calibre escapes a comma inside a single author name and GET /kosync/export handed the stored form out unchanged. Any service ingesting the export was matching against a name no catalogue lists. The rest of the app already un-escaped it; the export now does too.

• Firefox no longer draws permanent scrollbars down the side of the page. Firefox 153 changed how it treats one of the scrollbar rules the app was using, and the effect landed the day people updated: bars that used to fade away when you stopped scrolling became fixed, always-on, and squeezed the content beside them. In the new interface that hit the sidebar and the Discover row; the classic theme had the same thing on both columns of every page. Both are fixed — the app now describes scrollbars using the standard properties, so Firefox goes back to its own fading scrollbars, and the slim dark styling is unchanged in other browsers. Reported by @chloeroform (#1089).

• Adding the library to an iPhone or iPad home screen now gives you the app icon instead of a screenshot of the page. Every page offered iOS an .ico file as its home-screen icon, and described it as a size that file does not contain. iOS cannot use an .ico there, so it gave up and used a thumbnail of whatever page you happened to be on. The correctly sized icon had been sitting in the app unused the whole time; every page now points at it, and the same fix applies to the new interface and to servers running behind a reverse proxy on a sub-path.

Removed

• The two leftover app icons that nothing used are gone. cps/static/icon.png and icon.svg were the icons used before favicon.ico replaced them, and nothing had pointed at them since. They were still being shipped in every release, so every download carried about 29 KB of files no browser ever asked for. Reported by @chloeroform (#1095).

Changed

• The Russian interface is now complete — the last two English strings are translated. The "Support Calibre-Web NextGen" link added to the user menu in v4.1.20 was the only text left untranslated in Russian, so it showed in English next to an otherwise fully Russian menu. Russian is now the only language in the app with every string translated and nothing falling back to English. Contributed by @standhaftsohnsergius (#1088).

[v4.1.20] - 2026-07-24

Added

• The classic interface now has a way to support the project. There was no link anywhere in the classic UI — only the new interface had one — so anyone who wanted to chip in had to go looking for it. There is now a "Support Calibre-Web NextGen" entry in the user menu, in both the default and caliBlur themes.

Fixed

• The new UI no longer signs you out when a request doesn't make it through. Clicking between shelves could spin and then drop you on the sign-in page, and signing back in didn't help for long — "remember me" included. The new UI treated any request that failed to reach the server as proof your session had expired, and it responded by ending the session for real, so one dropped request on a busy or slow server logged you out for good. It now checks whether you're actually still signed in before doing anything, and a request that simply didn't get through is reported as an error instead. Sessions that genuinely have expired still return you to the sign-in page as before. Reported by @mrfearless (#1067).
• The edit page no longer jumps around when you rate a book. On the new UI's edit page, the Languages field was 8 pixels wider while a book was unrated and snapped back the moment you clicked a star, so the row visibly shifted every time the rating changed. The stars now take the same space in both states. Reported by @KucharczykL (#1064).
• Star ratings can be set again on the new UI's edit page. Clicking a star did nothing on an unrated book, and wiped the rating on a book that already had one — so there was no way to rate a book from the editor at all. Clicking now sets the rating you aimed at (half-stars included), and it saves with the rest of the form. Reported by @KucharczykL (#1061).
• Faster startup on large libraries. On a big library the container could sit for several minutes on boot before the app came up — the startup step that locates your library and settings database scanned every file under /config and /calibre-library on each start. It now checks the usual location first and only falls back to a full scan when a database isn't where it's expected, so most installs boot in seconds. Diagnosed and first patched by @chloeroform (#1022, #1075).

Changed

• The new UI now reads fully in Russian. The duplicate-scan controls added in v4.1.19 and the annotation-sync task labels had no Russian translation yet, so Russian users saw those in English. They are now translated, along with a spelling correction in the Kobo delete warning. Contributed by @standhaftsohnsergius (#1058).
• Brazilian Portuguese now covers the new UI. Large parts of the new interface — the cover picker, smart shelves, search filters and the sign-in screen — had no Brazilian Portuguese translation and fell back to English. 106 of those strings are now translated, and the smart-shelf button reads "Criar estante inteligente" so it matches the word used for shelves everywhere else. Contributed by @pedronora (#1072).

[v4.1.19] - 2026-07-21

Changed

• The new UI now reads in Brazilian Portuguese. Around 120 strings added in recent releases had no pt-BR translation yet, so Brazilian Portuguese users saw them in English — reading progress, the cover picker, the account and profile actions, and most of the task and error messages. All of them are now translated, along with a handful of corrections to existing wording. Contributed by @pedronora (#1021).

• The container no longer re-installs Calibre on every start. Each boot ran a Calibre installation step, on a container that already had Calibre in it — about 12 seconds of a one-minute startup on the hardware where this was reported, roughly two on a fast machine. The binaries did ship in the image; what was missing were the shortcuts that let the startup check find them, so the check failed and the install ran again. Those shortcuts are now built into the image, the check passes, and the step finishes in well under a second. Nothing about how Calibre itself works changes, and the step still repairs an image that turns up without them. Reported and originally patched by @chloeroform (#875, #1014).

Added

• Smart shelves can be marked for Kobo sync from the new UI. Ordinary shelves have had an "Enable Kobo sync" button on the shelf page since the new UI arrived; smart shelves did not, so the only way to set it was to open the rule editor and re-save the whole shelf. The button is now on the smart-shelf page too, next to Edit and Duplicate. It appears when your server has Kobo sync on and an admin has enabled "Sync Magic Shelves to Kobo", so it never shows up as a control that cannot do anything. Reported by @auspex (#867, #870).

Fixed

• You can run a duplicate scan from the new UI again, and the Admin panel's duplicate entry now opens the settings. The new interface had no way to start a duplicate scan at all: the button lives on the classic duplicates page, which the new one replaces, and the empty "a full scan is needed" notice told you to run it from CWA settings — a page that has no such button. The Duplicates page now has its own "Scan for duplicates" button that starts the scan in the background and tells you when it's queued. Separately, the Admin panel's "Duplicate Books" row opened the same page as the sidebar link, so it did nothing new; it now opens the duplicate-detection settings, where the matching rules, scan schedule and automatic-resolution options are. Reported by @auspex (#1048).

• Anonymous browsing works again in the new UI. With "Enable Anonymous Browsing" turned on, visitors were still stopped by a sign-in screen and could not reach the library at all — the classic view let them straight in, so the only way round it was to switch back. The new UI asked the server who you were, the server refused to answer for a guest, and the UI took that as "not allowed in" even though every other request would have been served. Guests now reach the library, and the account menu offers them a Sign in link instead of a sign-out and an account page they could not open. Sites without anonymous browsing enabled are unaffected and still require a login. Reported by @bentsea (#1023, #1045).

• Library sorting no longer merges distinct letters in Russian, Ukrainian, Greek and Japanese libraries. A recent diacritic fix stripped accent marks from every alphabet, so Й and И, Ї and І, ά and α, and が and か each collapsed into a single letter in the book list, the A–Z filter and OPDS feeds. Accent folding now applies only to Latin text. (#521)

• Smart-shelf pages now warn you when a Kobo-sync mark isn't doing anything. Marking a shelf for Kobo sync has no effect while your account is still set to sync your whole library to the device. Ordinary shelves already explained this; smart shelves didn't. The same note, and its one-click "Sync only my selected shelves" button, now appear on the smart-shelf page too. Originally reported by @auspex (#866).

• The web interface no longer checks for duplicate books every 2.5 seconds, all day, on every open tab. Any page you left open kept asking the server whether duplicates had been found — around 1,400 requests an hour per tab, on a library where nothing was happening. It filled up reverse-proxy logs and did needless work on the server. The check now runs when a page loads, when you come back to a tab, and while a duplicate scan is actually running (backing off as the scan goes on) — and stops as soon as there is nothing left to wait for. The duplicates badge and notification still appear on their own when a scan finishes. Reported by @blurrycontour (crocodilestick/Calibre-Web-Automated#1288), with a patch proposed by @budget-coder (#1018).

• KOReader highlight syncs no longer say "Server push failed", and the whole server no longer freezes while a highlight is sent to Hardcover. With "Sync Kobo annotations to Hardcover" turned on, every highlight in a book was sent to Hardcover one at a time while your device waited, and the server stopped answering anything — other people's page loads included — for about ten seconds per highlight. A book with a few highlights blew past the reader plugin's own time limit, so the device reported a failure for a sync the server had actually saved, and long freezes could make the container's own health check give up and restart it. Highlights are now saved and confirmed to your device immediately, and the Hardcover half runs in the background, where a slow or unreachable Hardcover can't hold anything up. Measured on the same machine: sending three highlights went from 30.2s to 0.13s, and an unrelated page load during that sync from 29.0s to 0.01s. Reported by @iroQuai (#920, #699).

• Kobo sync no longer occasionally un-downloads books from a magic shelf and takes your highlights with them. If you sync only selected shelves and one of them is a magic shelf, a book you already had on the device could sometimes come back with the download arrow on it; re-downloading it lost the annotations and highlights you had made. The sync was working out which books belong to a magic shelf by loading each book's full record, and if the library database happened to be mid-rewrite at that moment — which the automatic ingest does routinely — a few books quietly failed to load and were treated as "no longer on the shelf", so they were archived off the device. Shelf membership is now read from the shelf's own book list, which does not depend on the library database being readable at that instant. Reported by @TheDarkSpock and @bigbold1023 (crocodilestick/Calibre-Web-Automated#1307).

[v4.1.18] - 2026-07-20

Added

• Export all your KOReader reading progress as JSON. A new read-only endpoint, GET /kosync/export, returns every book you have reading progress for — Calibre book id, title, authors, percentage, and when you started and last updated it — so you can feed your progress into another service (for example a unified media tracker). It authenticates the same way as the other KOReader sync endpoints (HTTP Basic, app passwords supported) and only ever returns your own progress, limited to books you're allowed to see. Example: curl -u 'user:APP_PASSWORD' https://your-instance/kosync/export. Contributed by @Kyraminol (#978).

Changed

• The new UI is fully translated into Russian again. A dozen strings added in recent releases had no Russian yet, so Russian users saw them in English — among them the account and Kobo shelf-sync settings, the format picker and converter, and the "Something went wrong" error screen. All of them now read in Russian. Contributed by @standhaftsohnsergius (#1012).

• Startup logs now show where the time goes. If your container takes a long time to come up, docker logs --timestamps <container> used to show long unexplained gaps, because two of the startup steps never said when they began — you couldn't tell whether a step was running slowly or hadn't started yet. The library-mount step and the web server now both announce themselves as they start, so every second of boot is attributable to a named step. Reported and originally patched by @chloeroform (#1002), while investigating slow startup for #868.

Fixed

• Marking a shelf for Kobo sync now actually works — and the new UI tells you what else it needs. Turning on "Kobo sync" for a shelf does nothing until your account is also set to sync only selected shelves; until now nothing said so, so a device would keep paging through the entire library instead of settling on the shelf. The shelf page now says it right where you make the mark, with a one-click switch and a note that books off the shelf leave the device but stay in your library. Separately, turning that account setting on used to leave your reader syncing everything anyway — the new UI skipped the step that tells the device to drop the shelves you are no longer syncing, and the step itself worked against the sync rather than with it: it quietly removed the server-side record of what your device already had, which is the only thing the next sync uses to tell the reader to let those books go. So the books stayed on the device permanently, and were hidden from your library here into the bargain. The next sync after you turn the setting on now removes exactly the books that are not on a shelf you selected, and leaves everything else — on the device and in your library — alone. Reported by @auspex (#866).

• Switching a user to "sync only selected shelves" from the admin user list now takes effect properly. Admins can flip that Kobo setting from the column in the user table as well as from the user's own settings page, but only the settings page told the reader to drop the shelves it should no longer be syncing — set from the table, the device kept every collection until someone toggled it again from the other screen. Both routes now do the same thing, whether you change one user or select several at once. Saving from the user table also tells you when a save fails instead of reporting success and quietly discarding it. Originally patched by @Sanjays2402 (#1010), following on from #866.

• A page that hits an error no longer blanks the whole new UI. If anything went wrong while a page was drawing — a smart shelf that would not open, or a reader whose files could not be fetched after an upgrade — the new UI went completely blank. There was no message and no way back, so the only escape was to close and reopen the browser. Any such error is now caught and shown as a short "Something went wrong" screen with Reload and Back to library buttons, plus the technical detail if you want to include it in a bug report. Navigating away clears it. Reported by @monimkxl-web (#855).

• Book covers no longer blend into the page. A cover whose own artwork background happens to match your theme's background used to lose its edges and look like it was floating loose on the page. Every cover now has a thin outline in your theme's colour — in the library grid, on the book page, in the Discover and "More by this author" strips, in the table view, and in the duplicate list. Reported and originally patched by @chloeroform (#987).

[v4.1.17] - 2026-07-19

Added

• Series name and number are back under the book covers in the new UI. If your library is organized into series, each book card in the library, search results, and shelves now shows its series and position (for example "Dune #2") under the title and author, so you can see at a glance which series a book belongs to without opening it. The series-heavy library view already showed the position badge; this restores the series name that the classic view had. Requested by several users through the in-app feedback form (#657).

Changed

• Convert on the book edit page now offers a dropdown of valid target formats instead of a free-text box. The control reads "Convert from [EPUB] to [MOBI]", the source list is limited to formats the configured converter can read, and the target list excludes the already-selected source.
• Faster container startup, less disk churn. On every boot the container was re-setting ownership across the entire application tree — around 1,800 files — which took anywhere from a couple of seconds to half a minute depending on your hardware, and on some storage back-ends copied every one of those files into the container's writable layer. The application code is read-only and already readable by everyone, so almost none of that work was needed. Startup now re-owns only the handful of folders the app actually writes to (metadata change logs and export temp), leaving the static code untouched (#941). Reported by @auspex and @chloeroform.

Fixed

• The Library remembers your sort order and read filter after a refresh. In the new UI, changing the Library sort (for example to "Author A–Z") or the read-status filter (Unread/Read) no longer resets to the default when you reload the page — your choice is kept per browser and restored on the next visit. Series, author, and other scoped views keep their own natural ordering as before. Reported by @standhaftsohnsergius (#640).

• “Read now” actions now form a straight bottom row across New UI book cards on iPad and other touch devices. Short titles reserve the same two-line space as long ones, while shelf removal and quick edit are no longer hidden behind hover on touch hardware. Desktop keeps its uncluttered hover treatment, with keyboard focus revealing the actions. Thanks @Andrew-H2O (#863).

• Dismissing the duplicate-scan setup notice no longer fails silently. On a standard container, clicking to dismiss the one-time "run a full duplicate scan" notice returned a server error and the notice kept coming back, because the app tried to record the dismissal in a location it isn't allowed to write to. The dismissal is now stored on your config volume like other per-user settings, so it sticks and survives upgrades (#992).

[v4.1.16] - 2026-07-17

Added

• You can now support CWNG development from the app — announcements queue in the top banner, and clicking anywhere on the Ko-fi message opens Ko-fi and dismisses it; dismissals are remembered. A Support on Ko-fi link is also available in the Help menu.

Fixed

• GitHub releases include the KOReader sync plugin again. The cwasync.koplugin.zip download disappeared after v4.1.11 even as three plugin fixes shipped, so people installing from the release page could not get the current plugin. v4.1.16 restores the ready-to-install archive and identifies the bundled plugin as version 4.1.16. Thanks to @KucharczykL for flagging the missing asset in #400.

• Brazilian Portuguese now covers ~150 more of the interface. Strings across the reader, shelves, and admin screens that still showed in English — including the "New" badge — now appear in Portuguese, and four entries that displayed the wrong text are corrected ("Shelf duplicated successfully" had been showing the message for deleting users; "Read Status" now reads "Status de leitura"). Translation work by @pedronora (#949).

• Russian is now fully translated. The last 48 English strings — renaming a tag and its error messages, smart-shelf rule failures, page-not-found and page-load errors, and the Hardcover token-file notice — now appear in Russian, and a fuzzy entry on the Hardcover notice is confirmed. Translation update by @standhaftsohnsergius (#970).

[v4.1.15] - 2026-07-17

Fixed

• KOReader stopped seeing new versions of the sync plugin. If you update the plugin from inside KOReader — through Updates Manager or appstore.koplugin — the newest version it offered was the one from 13 July, even though three plugin fixes have shipped since: highlights and notes syncing into your library, highlight deletions syncing to the server, and a guard that stops a device deleting highlights it never had. The plugin releases those tools read had quietly stopped being published, so the fixes were in the server but never reached the device. The current plugin is published now, and publishing it is no longer a manual step that can be missed. If you install the plugin by downloading it from your own server's KOReader page, nothing changed for you — that copy was always current. Thanks to @KucharczykL for spotting it and to @filiporlo for #400.

• Books with two or more authors were hard to read in the new UI. Authors were separated with a comma — but an author's name can contain a comma itself ("Dumas, Alexandre"), so two authors came out as "Dumas, Alexandre, Maquet, Auguste" and you could not tell where one person ended and the next began. Authors are now separated with "&", the same way the classic interface, Calibre itself, and the new UI's own edit box ("Authors (separate with &)") have always done it — so the book page, the library grid and the table view now agree with the edit form instead of contradicting it. Tags, languages and publishers are unaffected and still use commas. Thanks to @chloeroform for the report.

• New accounts ignored the default theme you picked in Admin. Whichever theme an admin chose under Admin → Theme, some new accounts still started on Dark. Which accounts depended on how they signed up: people who registered themselves through the new UI got it wrong only on servers upgraded from an older build, while accounts created by OAuth, LDAP import, or an external/proxy login always got Dark no matter what you had set — those three still carried a hardcoded default from back when Light was removed, and were never updated when the six themes returned. Admin-created accounts were always fine, so the same setting could produce two different results on one server. All seven ways an account can be created now seed the theme you configured.

• "Change cover" made the whole server unreachable until it finished. Opening the cover picker on one book froze every other page for everyone using the server — up to about 12 seconds, however long the slowest metadata source took to answer. The same freeze hit the "Search metadata" button on the edit page. Measured on a test library: a book page that normally answers in 30ms took 11.4 seconds while a cover search ran; it now answers in well under a quarter second, and the cover search itself is no slower. Thanks to @darkmatterpelican for reporting it in #954.

• Setting a default library view turned your library into the search page. After saving a default view, the library home showed the "Advanced search" form pinned above the books, the page was retitled "Advanced search", and the library heading, its actions and the Discover strip disappeared. Your library now stays your library — it simply shows the books your default view selects, with a note saying so and a "Show all books" link to see everything again. Reported by @chloeroform.

• Automatic duplicate resolution never ran if you set a cooldown. Turning on the cooldown ("wait N minutes between automatic resolutions") stopped automatic duplicate resolution from running at all, and the log reported a wait of about four hours counting up rather than down. Two separate causes: the cooldown you typed was thrown away and replaced with one minute, and the clock comparison mixed your local time with UTC, so the wait never elapsed. If your server runs east of UTC the opposite happened — the cooldown was ignored and resolution ran on every scan. Both are fixed and your existing resolution history stays intact. Thanks to @jdbway, who diagnosed both causes and pinpointed the exact lines in #944.

• Startup no longer sets permissions on your Calibre library twice. Every container start walked the whole library once from a hardcoded list and again from dirs.json, and re-walked a folder inside /config that had already been covered. Each folder is now visited once, which shortens startup on large libraries. Thanks to @chloeroform for spotting it in the startup log and measuring it.

• Russian screen readers announced the reader's progress as "Прочитано: 45% r" — a stray letter left over from the English "read". It only ever reached people using a screen reader, since the text is spoken rather than drawn on screen. Brazilian Portuguese was already correct and is unchanged.

[v4.1.14] - 2026-07-16

Added

• You can now hide books from your personal library in the new interface without deleting them or affecting anyone else. Hide/Unhide lives beside Delete on book details, and View settings can reveal clearly marked hidden books whenever you want one back. The feature is on by default for new installations; upgrades preserve the admin's existing Allow users to hide books switch, which is the kill switch to check if Hide is absent.

Fixed

• Translated entity pages now say “Show all authors/tags/…” in the signed-in user's language instead of leaking the English route segment, and locale- sensitive search labels now lowercase using the app language rather than the browser's language. Most-downloaded lists also remain usable for libraries large enough to exceed SQLite's single-query parameter limit.

• Brazilian Portuguese users now see more of the New UI in Portuguese, including book actions, upload feedback, favorites, and hide/archive status; stale catalog entries and misleading action/toast wording were corrected during adoption. Translation update by @pedronora (#865).

• Russian users now see the newly added New UI controls, smart-shelf date filters, theme choices, upload flow, and accessibility announcements in Russian instead of English fallback text. Translation update by @standhaftsohnsergius (#895), with terminology corrections during adoption.

• New UI translation updates no longer manufacture fuzzy guesses that look complete but disappear at runtime. Legacy SPA guesses are now an explicit untranslated review queue, an all-locale gate prevents fuzzy entries from returning, and reviewed French, Russian, German, and Hungarian navigation, shelf, status, error, and accessibility text now renders in those languages. Built-in smart-shelf names also follow the signed-in user's language without renaming the shelf (#879, #886).

• Hardcover setup no longer hides token status behind a disabled sync switch, points secret-file users at the wrong environment variable, or shows two conflicting enable checkboxes. One server-wide switch now controls both reading-progress sync and scheduled Hardcover ID fetching, existing enabled installations are preserved during migration, and compose deployments can manage it with HARDCOVER_SYNC_ENABLED. Startup logs report enabled/token presence and their sources without exposing the token. (#897, #898, #899, #900)

• Classic catalog cards now use the same read checkbox state as book details: checked means read and empty means unread, while the tooltip still names the action clicking will perform. Thanks @darkmatterpelican for the cache-free, list-versus-detail reproduction (#771).

• Dismissing the classic-view “Try the new UI” banner now keeps it dismissed after updates. It is a one-time adoption cue, not a What's New notice, so a previous version-specific dismissal is migrated to one durable browser choice. Thanks @darkmatterpelican (#907).

• Advanced server settings now say before you click that they open in the classic view. Those deep configuration pages intentionally remain in the proven server-rendered interface during the hybrid cutover; the New UI no longer makes that transition look accidental. Thanks @HLRobius (#909).

• Series, tag, author, publisher, and language pages now put their real name in the browser tab. Direct links previously captured the … loading state before the entity query finished and never refreshed it. Thanks @chloeroform (#892).

• Tags can now be renamed from their New UI page. Editors previously reached a read-only tag page with no rename action; the corrected name now updates the shared tag in the library and every linked book. Thanks @chloeroform (#914).

• Signing in through the new interface now opens the requested page instead of showing “This page doesn't exist here.” Password and magic-link logins honor safe same-site destinations, fall back to the library when no destination was supplied, preserve reverse-proxy subpaths, and reject links that try to send the browser to another site.

• Syncing highlights from a second KOReader device no longer wipes the highlights from your first one. Opening a book on another device could silently delete every highlight the other device had made, permanently and with no error — a later sync never brought them back. Deleting a highlight on a device still removes it everywhere, which is what this path is for; the device now says which highlights the user deleted instead of the server guessing from what a sync left out. Caught before release, so no published version ever shipped it (#920).

• Deleting a KOReader highlight now actually syncs. The fix released for this in v4.1.13 never reached the server: the plugin set the field, but its request spec did not list it, so it was dropped before the request was sent and the deleted highlight stayed in your library. Update the plugin to 4.1.14 (Highlight sync → the plugin ships with this release) for device deletions to sync (#905, #906).

• Admin → Theme no longer says "Settings saved." and then changes nothing. The picker stored its choice in an old numbering the theme system stopped reading, so "Light" always came back dark. It is now the default theme for new accounts, it offers every theme (System, Light, Dark, Sepia, High contrast, Midnight) instead of just two, and a "Light" you saved earlier is honoured rather than discarded. Your own theme stays where it belongs, under Account → Theme. Thanks @auspex for reporting it and pushing back when the first fix missed the part you filed about.

• KOReader progress now appears on both classic and new book pages even when the book already had a read/unread record before its first matched sync. The devices could exchange positions while the web page showed no “KOReader Progress” entry because that existing-row path never created the separate bookmark state the pages display. This is a server-side fix; no device plugin update is required. Reported and carefully re-tested by @uschi1 (#627).

• Signing out no longer drops a browser that prefers the New UI onto the classic login page. The anonymous login state now honors the same durable, per-browser interface choice as the signed-in library, while new browsers, non-HTML clients, disabled-SPA instances, and reverse-proxy subpaths keep their existing behavior. Thanks to @iroQuai for reporting the logout gap after the separate #807 login-label fix. (#908)

• The classic smart-shelf editor now actually offers working “In the past N days” and “Not in the past N days” choices for Publication Date and Date Added. Both editors now read the same rule schema, preventing fields and operators from silently drifting apart again. Reported by @Glennza1962 (#467).

• KOReader: deleting a highlight on your device now removes it from Calibre-Web NextGen too. Previously the highlight stayed in the book's highlights list forever, however many times you synced. Reported by @iroQuai (#905). Update the NextGen Progress Sync plugin on your device to pick this up.

[v4.1.13] - 2026-07-14

Added

• Metadata searches for English and Dutch books can now find Goodreads and bol.com results after you opt in to their clearly labeled best-effort providers. Both are off by default, require no API key, use hard request timeouts, and leave other enabled sources working if either website blocks a request or changes its pages. (#303, #315)

• Platform-specific install and switch guides now cover Synology, Unraid, Portainer, TrueNAS SCALE, QNAP, Dockge, and Docker Compose, with verified first-run screenshots, safer migration guidance, and matching generated-wiki pages. Contributor documentation now also explains the supported local-development workflow and pull-request quality checks. (#527, #843, #765)

• Book details and the sortable table now show when each book was added and last modified, restoring metadata that was only visible in the classic interface. (#878)

• Libraries that need a standing filter—such as hiding comics by tag—can now save any advanced search as the account's default library view, with the choice following the user across devices and a one-click way to clear it. (#498)

• KOReader highlights and notes from the open book can now sync into Calibre-Web NextGen, survive concurrent updates from multiple devices, and appear in the existing Highlights list on the book page. (#699)

Changed

• Editors can now correct a book title directly in the sortable table with keyboard-friendly Save/Cancel controls, while viewers retain a read-only table. (#783)
• The new in-browser reader now keeps font family, size, margins, line height, and page theme with your account, so your preferred reading layout follows you between browsers and the classic/new interfaces; its appearance panel is touch- and keyboard-accessible on phones and desktops.
• Book grids can now load a chosen number of complete rows at any card density, Discover respects the server's random-book count, and touch-screen “Read now” actions align along the bottom of each card.

Fixed

• The Fetch Metadata window's Keys panel now shows Hardcover as "Configured" when the token comes from the HARDCOVER_TOKEN environment variable or a HARDCOVER_TOKEN_FILE secret, instead of claiming no key was set. Searches worked the whole time — only the badge was wrong, which made a working setup look broken. (#896)
• Hardcover auto-fetch now records what each run did, so the Stats & Activity page's Hardcover section shows the books processed and matched instead of staying blank. Runs still finished their work before, but every one of them logged "Error saving stats to database" and saved nothing. (#876)
• Changing one classic-reader appearance control no longer erases the user's other saved reader settings.
• The classic book page's favorite star now changes immediately after a click instead of waiting for a reload, because object-shaped action responses no longer crash the shared flash-message handler. (#880)
• Smart-shelf moving date windows are now available in the new interface's rule builder—not only the classic builder—with Publication Date and Date Added fields and day-based operators. (#467)
• Reload metadata now reads PDF, FB2, comic, audio, EPUB, and KEPUB files instead of failing through an EPUB-only path, and applies only the details a file actually contains — a book whose file carries no title or author keeps the title and authors you curated instead of being renamed after its filename. Editors can also run it from the new book page. (#877)
• Uploading a PDF now picks up the author recorded inside the file. PDFs without an XMP block — most of them — previously imported as "Unknown" even when the file said who wrote it. (#877)

[v4.1.12] - 2026-07-13

• Newly imported books now sync KOReader progress immediately in filename-matching mode. A book added after server startup could report “No book found” until it was downloaded once or the server restarted, leaving progress detached from the web UI and other devices. Both document identities are now registered as part of ingest. (#509, #627)
• A replaced side-loaded book no longer stays duplicated in a Kobo's My Books list after the old copy is deleted. Hard-delete sync now uses the full archive/removal response Kobo firmware honors, while preserving official Kobo-store sync responses and hiding the dead entry from Archive. (#832)

Added

• Mobile libraries can show two, three, or four complete covers per row instead of spending the whole screen on one book. Library View settings now offer Comfortable, Compact, and Dense layouts, remember the choice in that browser, and use more of wide desktop screens without cropping cover art. (#835, #764)
• Series pages no longer force every book into the cover grid. A keyboard- and touch-accessible grid/list switch provides a more readable alternative and remembers the choice. (#662)

Changed

• Long tag collections no longer push a book's description several screens down on mobile. Book details now keep the cover and useful title information together, collapse tags after the first eight behind an accessible Show all control, and show synced reading position as a semantic progress bar. (#836)
• Magic-link and SSO choices no longer stretch the login page into separate sections. Every configured method now appears in one compact “Login with” row, including all enabled providers under their configured display names. (#833)

Fixed

• High-resolution Amazon covers remain available when the Amazon metadata provider is turned off. The cover picker now uses a book's stored ISBN to offer the high-resolution image independently, so unreliable Amazon metadata can stay disabled without losing the cover source. Thanks to @briffaantoine for identifying the missing configuration path. (#304)
• Russian and French no longer fall back to English across several new-interface menus. Data-driven sidebar, Admin, filter, and sort labels now enter the translation catalogs just like directly translated text; Russian gains the remaining menu translations, French gains the library/search/sort translations reported in #615, and the classic database troubleshooting guide is now translatable. Credit: @standhaftsohnsergius (#844). Addresses #719 and #615.
• A hidden Table view can be restored without switching back to the classic interface. Customize navigation now includes the same server-backed “Show book list” setting that controls the Table link. (#837)
• The new book page shows the real imported filename again instead of losing it—or showing an internal timestamp/random staging prefix after a browser upload. Uploads now carry the browser-selected name explicitly through ingest, and the SPA displays that stored name as “Imported as.” (#840)
• Reloading metadata now refreshes stale EPUB/PDF/other format sizes too. The refresh rechecks every real file on disk and persists changed sizes, so a conversion or external replacement no longer leaves an obsolete size blocking Send to eReader. (#841)
• Shelf actions no longer push the page wider than a 375 px phone screen. Rename, visibility, Kobo, reorder, and delete controls now wrap inside the shelf instead of creating horizontal scrolling.

[v4.1.11] - 2026-07-12

Added

• The most-requested Light design is here, as part of a complete per-account theme system. Open Account → Theme in the new interface to choose System (follows prefers-color-scheme and switches live with your device), Light, Dark, Sepia, High contrast, or Midnight (true-black for OLED screens). The choice applies instantly, belongs to your account rather than the whole server, and survives reloads, signing out and back in, and server restarts. Light and Dark hold across the whole SPA — library, book details, editor, Admin, dialogs, status messages, and reader chrome — with WCAG 2.2 AA contrast; High contrast goes further for low-vision reading. Thanks to @uschi1 and @auspex for pushing this to the top of the list (#351, #736).
• Admins can reset another user's password without leaving the new UI. Eligible user cards now offer a confirmed, admin-only reset that generates the replacement on the server and emails it to the user's existing address; the browser never receives the password, non-admin/Guest/self targets are rejected, and a mail-queue failure leaves the old password usable. (#745)
• Readable books now have a one-click Read now action on their grid card. It opens EPUB/KEPUB in the new reader and supported PDF, comic, text, and audio formats in their in-browser reader, while the main card still opens book details. The action is always visible on touch screens and fully named for keyboard and screen-reader users. (#653)
• Smart shelves can now use moving date windows such as “in the past 28 days.” Publication Date and Date Added rules support both “In the past N days” and its inverse, so a shelf for the past four weeks or six months keeps itself current instead of freezing a date into the rule. Invalid, empty, negative, and excessively large windows are rejected safely. (#467)
• The new book page now shows Calibre custom columns such as Pages. Every displayable custom field shown on the classic detail page is carried into the redesigned page with its correct type and formatting, while ignored fields and the configured read-status column stay private/unduplicated. Zero and “No” values are preserved instead of disappearing. (#767)
• Admins can edit the send-to-eReader email body from the new Account page. The redesigned page already exposed the recipient and subject but omitted the classic global message-body template. Admin accounts now get the missing localized textarea; non-admin accounts cannot read or change the server-wide template. (#834)
• Basic Configuration now shows whether the active Hardcover token is present, accepted, and expiring. A rejected token no longer requires log archaeology: the admin page distinguishes missing, valid, rejected/expired, and temporarily unverifiable states, and shows the expiry when the token provides one. (#838)

Changed

• Upload is now a distinct Library action instead of another identical sidebar row. Accounts allowed to add books get a clearly named, touch-sized Upload books button in the Library toolbar on desktop and mobile; direct /upload bookmarks still work. Admin also has one conventional home in the account menu instead of a duplicate sidebar link. (#664, #722)
• Customize navigation no longer dominates the top of the sidebar. The oversized glass capsule has become a quiet, touch-sized footer control beside the navigation it changes, while the existing keyboard/touch reorder flow, focus restoration, reset, and status announcements remain intact. (#714)
• The Library no longer shows two search boxes that do the same thing. Simple search now lives in the top bar on desktop and its focused search row on mobile; the Library still keeps Advanced Search for richer filters, and the top-bar field stays synchronized with deep links and browser back/forward navigation. (#723)
• Books without a cover now show a clean Calibre-Web NextGen placeholder instead of the old logo card. Coverless books used to display a generic dark logo image that looked out of place — especially on the new Light and Sepia themes. In the new interface they now get a tasteful typographic cover (the book's title and author on a card that matches your theme); the classic interface, OPDS, and Kobo get a refreshed NextGen placeholder image. Real covers are unchanged.

Fixed

• Expired reverse-proxy sessions now return you to the login page instead of a dead screen, and Sign out logs you out of your proxy too. With Authelia/OIDC/oauth2-proxy in front of the app, leaving the new UI open until the login session expired showed a "Failed to fetch" error on the next action instead of bouncing you back to the login page. And Sign out only cleared the app's own session, so a reverse proxy that ends its login on a top-level /logout request never saw one — you could stay signed in at the proxy. Both are fixed: any expired-session response now returns you to the login page, and Sign out makes the real top-level /logout request the proxy can act on (the reverse-proxy sub-path is preserved). Thanks to @auspex for the report (#824, #674).
• A theme that failed to save no longer looks as though it succeeded. If the server rejects the change, the picker, live preview, and local reload cache now all return to the account's saved theme instead of leaving an unsaved palette active.
• Light mode now stays visually consistent in Admin, book-card actions, the cover picker, and the EPUB reader. Native Admin dropdowns no longer fall back to square browser-default styling, controls layered over cover art use a guaranteed-contrast backing, and the reader's toolbar follows its Light/Sepia/Dark reading surface instead of always remaining dark. Addresses #351.
• Shuffling the new UI's Discover picks no longer makes the Library jump up and down. The existing cards stay in place while a fresh random set loads, then update in one step; screen readers are also told when the shuffle starts and finishes. (#850)
• Uploading books in the new UI now uses the browser's native, keyboard-accessible file control. Drag-and-drop and tap-to-choose share one reliable control, repeat uploads are blocked while one is pending, and queued/rejected results are announced to assistive technology. (#654)
• Accented titles and names now sort with their base letters in the library, search results, the new UI, and OPDS. È/É entries no longer fall to the end or get stranded in separate letter buckets; composed and decomposed Unicode forms agree, Spanish Ñ remains a distinct letter after N, and German ß receives ss primary ordering — all without adding a native collation dependency. (#521)
• One pathological PDF download no longer freezes every other page for up to 90 seconds. Calibre metadata exports now run in a bounded gevent-aware thread pool, so health checks and unrelated requests remain responsive while a slow export waits; excess exports immediately serve the original file instead of building a queue. Timeout and process-tree cleanup remain intact. (#561)
• Book covers show the whole cover again instead of being cropped. In the new interface, covers whose artwork isn't a standard 2:3 shape had their edges cut off to fill the card. Covers now fit the whole image inside the card (letterboxed on a matching background), and the cover picker shows the complete artwork when you're choosing between editions — the grid layout and density are unchanged. (#660)
• Searching after editing a book now shows the corrected details. After you changed a book's title or author in the new UI, searching could still turn up the old value. The library now refreshes its in-memory view when you save an edit, so search reflects your change right away. (#744)
• You can reach your entire library, not just the first screenful. The new library grid loaded more books only as you scrolled, and if that automatic loading didn't kick in you were stranded on the first pages. There's now a keyboard-accessible Load more button that stays available whenever more books remain, so the whole library is reachable however you browse. (#704)

[v4.1.10] - 2026-07-11

Added

• You can delete a book from the new UI again. The redesigned book page had no delete control, so removing a book meant switching to the classic interface. The book page now has a Delete button (shown only to accounts with the "Delete books" permission) that asks for confirmation, then removes the book and its files just like the classic view — after which you're taken back to your library with the book gone from the grid. Thanks to @Glalith121 for the report (#803).
• The new UI's metadata-search dialog now has the per-provider on/off toggles. You can turn individual metadata sources (like Hardcover) off and back on directly from the new editor, just like the classic view — the choice is saved to your account, so it's the same whichever interface you use. (#677)
• Book ratings can now be set with an inline five-star control in the new editor. Click either half of a star for half-star precision, use the arrow keys to adjust in half-star steps, or clear the rating explicitly — no dropdown required. (#779)
• Authors, series, tags, publishers, and other browse pages now have a compact list view. Use the grid/list toggle to switch from cards to full-width name-and-book-count rows; the choice is remembered in this browser, including on mobile. (#697)
• The new UI's book editor has a Publication date field again. The redesigned editor shipped without the publication-date field the classic editor has, so the date could only be set from the classic UI. The editor now has a "Published" date input — prefilled from the book's current date, and clearable to reset it. This completes the #689 report alongside the metadata autocomplete that shipped in v4.1.9. (#689)

Fixed

• The new UI's login page now shows your configured OIDC/SSO button label. With OpenID Connect login set up, the classic login page showed your admin-set "Button label" (e.g. "Continue with Acme Identity"), but the new interface's login button showed the internal provider name ("generic") instead. The new UI now reads the same configured label the classic page does, so both surfaces show identical SSO button text. Thanks to @thelastblt for the report (#807).
• Editing one book's metadata no longer floods the log with repeated "log file not found" warnings. Saving a single metadata change could make the background cover/metadata enforcer run several times over for that one change — the first run did the work and deleted its to-do note, and every later run logged a Log file '…' not found after 3 attempts / Skipping processing warning, up to six times per save. The change detector now collapses the burst of filesystem events a single save produces into one enforcement pass (both the inotify and polling watchers share one debounce now), and the already-handled case is a single calm note instead of a stack of warnings. Thanks to @auspex for the report (#802).
• Reading progress now carries over between the classic reader and the new UI's reader. Turning pages in one reader and then opening the same book in the other could resume at the beginning or an old spot. Both readers now save your position to your account continuously (not just when you tap the bookmark button) and, on open, resume from the newest position the server has — so you can switch interfaces mid-book and pick up where you left off. Libraries upgraded from older versions are repaired automatically on startup, and your last-read position still restores offline. Thanks to @Glalith121 for the report (#805).
• "Run Hardcover Auto-Fetch" now works instead of failing immediately. Triggering the Hardcover ID auto-fetch from settings could stop right after "Found N books…" with an internal "owning session has been closed" error, because the background job set up its database connection on the wrong thread. The job now opens its connection on the thread that actually runs it, so it works through your whole library — matching books to Hardcover and queuing uncertain matches for review — without crashing. (#821)
• Automatic metadata fetching during ingest no longer crashes when Hardcover is configured. When a book was imported through the ingest folder with automatic metadata fetching on and a Hardcover token set, the import could fail with an internal error because the ingest process read its configuration from a partial, hand-maintained list of settings — so a newer setting (here, the Hardcover token) was simply missing. The ingest process now loads the full configuration the same way the rest of the app does, closing that whole class of "missing setting" crash. (#819)
• Two people on the same server can now share one Hardcover token. Saving a Hardcover token that another account already used could fail with an internal server error, because each token had to be unique to a single user. Sharing one token across accounts is now allowed, and existing libraries are migrated automatically on upgrade.
• The library's default newest-first order now has regression coverage across the API and new UI. The default uses Calibre's added/modified timestamp (not publication date), and fresh catalog/filter mounts replace stale accumulated pages before rendering. (#753)
• Four remaining Russian interface strings are now complete in the new UI. Suggestions, library refresh, highlight removal, and returning to the new interface no longer appear untranslated or use a fuzzy mistranslation. (#656)
• KOReader sync no longer loses the furthest reading position when another device is behind. A later push from a different device on an earlier page could overwrite the server's further position, and device-clock differences could then classify a real forward sync as backwards. The server now keeps the highest known percentage across devices and file digests, while still accepting deliberate rewinds from the same device; marking a finished book unread also clears its KOReader server position so it can be restarted. The bundled KOReader plugin uses percentage—not clock order—to decide whether a remote position is ahead. Thanks to @Glalith121 and @mueslimak3r for the detailed cross-device reports. (#633)
• The new UI's send-to-e-reader dialog now shows your saved e-reader address instead of an empty recipient field. The recipient box was blank with only a "blank = your e-reader email" hint, so it looked like the address you'd saved in your account had been lost — even though sending still worked. The field is now prefilled with your saved address; type a different one to override it for that send, or clear it to fall back to the saved address. (#715)
• Reporting an issue from the new UI's Help menu now opens the bug-report form instead of a blank issue. The "Report Issue on GitHub" link pointed at the blank-issue URL, so reporters landed on an empty textarea rather than the Bug report / Feature request templates defined in the repo. It now opens the issue-template chooser. Thanks to @auspex for the report (#799).
• The edit pencil on a book card can now be opened in a new tab. In the new UI, the hover edit pencil on a book card was a button rather than a real link, so ⌘/ctrl-click (or middle-click) didn't open the editor in a new tab the way real links do — there was no href for the browser to open. The pencil is now a true link: a plain click still opens the editor in place (no full page reload), and a modified click opens it in a new tab. Thanks to @chloeroform for the report (#798).
• Hardcover metadata is fetched again when a book is auto-ingested. After the v4.1.9 change that centralised how the Hardcover token is read, the automatic fetch that runs on ingest aborted with an internal error and skipped Hardcover — even with a HARDCOVER_TOKEN set — while manual "Fetch Metadata" kept working. The token is now read safely in the background ingest process, so a HARDCOVER_TOKEN (or HARDCOVER_TOKEN_FILE) in the environment is applied during ingest again. Thanks to @ghub3297 and @Glalith121 for the reports (#819).

Fixed

• Saving a cover for a PDF-only or other non-EPUB/AZW3 book no longer ends with a false enforcement error. The metadata enforcer now preserves the successful cover save, refreshes the format-independent metadata.opf backup, and logs an informational note that only in-file embedding was skipped for the unsupported format (#797).
• Author-sort mismatch warnings now name the affected book and link straight to where you fix it. The warning previously omitted the book title/ID and pointed at an author-admin screen that doesn't exist, so there was no clear way to act on it. It now names the book and gives the direct edit link (/admin/book/<id>): opening that page and re-saving the book's Authors field regenerates its author sort and clears the warning (or you can correct the book in Calibre). Thanks to @auspex for the report (#801).
• The classic book page's read checkbox now matches the book's actual state. Unread books previously showed a checked box beside the “Mark As Read” action, while read books showed an empty box. The checkbox is now empty for unread and checked for read; its tooltip continues to describe what clicking will do (#771).
• OPDS readers now have a dedicated “Currently Reading” feed. The OPDS root previously offered only Read and Unread, forcing in-progress books into the broad not-finished group. Signed-in users can now open a feed containing exactly books in the canonical in-progress state, with the same visibility and selected-shelf restrictions as the rest of their OPDS catalog (#672).

[v4.1.9] - 2026-07-11

Added

• The new UI now has a Refresh library button, so a manual re-scan is one click away again. The redesigned library page shipped without any equivalent of the classic header's "Refresh Library" action, so after dropping new files into the ingest folder there was no way to trigger a scan from the new UI — the books just didn't appear until the next automatic sweep. The library toolbar now has a refresh button that starts the background scan, shows a status line while it runs, and refreshes the grid so newly-added books show up. Thanks to the reporters (#780, #665). (#780, #665)
• The new UI's book editor suggests existing tags, authors, series, publishers, and languages as you type again. When you edit a book's metadata in the redesigned interface, each of these fields now offers a dropdown of values already in your library, so a typo no longer quietly creates a near-duplicate tag (sci-fi vs scifi) or series. Pick from the list, or keep typing to enter a brand-new value — the classic editor's autocomplete is back. Thanks to @magdalar for the report. (#741, #778, #689)

Fixed

• The startup log no longer prints a scary "desktop integration failed" warning. On first container start, Calibre's installer tried to register desktop menus and MIME types — pointless in a headless server image — and printed a WARNING with a traceback that made healthy startups look broken. The standard directories the step expects now exist, so it completes silently. Thanks to @darkmatterpelican for the report (#769).
• The HARDCOVER_TOKEN environment variable now works everywhere. Setting the Hardcover API token via the environment used to be honored by some features but ignored by others — most visibly, the Fetch Metadata panel told you to "set a Hardcover API key" even though your env token worked, and the admin page gave no hint a token was active. All features now resolve the token the same way, the admin page shows a note when an environment token is in use, and you can keep the secret out of your compose file entirely with the new HARDCOVER_TOKEN_FILE (docker-secrets style). Thanks to @KucharczykL for the report (#743).
• OPDS feeds now show which letter or item you drilled into. Following up on the per-feed titles added in v4.1.8: an alphabetical sub-list now shows its letter ("Alphabetical Books (U)", "Authors (V)"), and opening a specific author, category, series, publisher, rating, file format or language names it in the feed title ("Categories: Fantasy", "Ratings: 4.5 Stars", "Languages: German"). The author/category/series letter lists — which still showed only the bare server name — are fixed too. Thanks to @chloeroform for the suggestion (#758).
• The Admin page's configuration buttons now open in the same tab. In the new UI, everything under "More server configuration" (Basic configuration, UI settings, Logs, Scheduled tasks, …) opened a new browser tab, piling up windows and making it look like the app had forgotten you switched to the new UI. These are in-app pages and now navigate normally. Thanks to @auspex for the report (#738).
• Choosing the new UI now sticks. Once you switch to the redesigned interface, the choice is remembered on that browser — opening the library, following a bookmark, or opening the page in a new tab lands you back in the new UI instead of silently dropping you into the classic view and showing the "Try the new UI" banner again. Switch back to classic (from the new UI's account menu) and that choice sticks too. The preference is per-browser, so other devices and other people on the server are unaffected. Thanks to @auspex for the report (#739).
• New UI reader: highlights can now be removed (and recolored). In the redesigned in-browser EPUB reader you could create a colored highlight by selecting text, but there was no way to delete one — tapping an existing highlight did nothing, so unwanted highlights piled up with no way to clear them. Tapping a highlight now opens a small menu: pick a different swatch to recolor it, or choose "Remove highlight" to delete it. Thanks to @hayvan96 for the report (#782).
• New UI: opening a shelf no longer shows a blank screen. On v4.1.8, clicking any shelf — a manual shelf or a smart (magic) shelf — in the new UI left the page blank, and refreshing the browser did not recover it. The main book list, authors, series and other pages were unaffected. Rolling back to v4.1.7 was the only workaround. This is fixed; shelves open and list their books again. Thanks to @mrfearless and @Gauva1n for the reports (#784).
• Half-star ratings no longer draw a tiny star floating inside the outline. In the new UI, a book with a half-star rating (3.5, 4.5, …) showed the fractional star as a shrunken miniature star sitting inside the empty outline on the book page. The partial star now fills cleanly from the left edge. Thanks to @KucharczykL for the report (#776).
• The new UI could keep showing outdated interface translations after you upgraded — for example the French read button reverting to English "Read now" and the "mark as read" toggle showing the wrong wording, even though the fix had already shipped. The interface-text file the new UI loads now refreshes whenever it changes, so an upgrade always shows the current translations (a hard browser refresh clears any that were already cached). (#615)

Changed

• The new UI now uses the readable System font by default for both headings and body text, instead of the bookish serif some readers found hard to read. If you prefer the old look, "Bookish Serif" is still one click away under Account → UI display/body font (it's now offered for headings too). (#641)
• German interface: 19 strings that showed in English now appear in German. The OPDS catalog descriptions (for example "Books sorted by series" and "Popular publications from this catalog based on rating") and the duplicate-scan progress messages were untranslated, so German users saw English there while the rest of the UI was translated. Filled in from pending German translations contributed upstream. Thanks to @djalexz85 and @fucx (Calibre-Web-Automated) and @ManuelDrescher (calibre-web).
• Ukrainian interface: 141 more strings now appear in Ukrainian. Error messages, the metadata review queue, the cover/thumbnail cache tools and other panels that previously showed English for Ukrainian users are now translated. Filled in from pending Ukrainian translations contributed upstream. Thanks to @Demelja (Calibre-Web-Automated).

[v4.1.8] - 2026-07-10

Added

• Book pages now show when you started reading and when your progress last synced. If you read with Kobo or KOReader, the book page now shows both dates so you can see how long a book has been in progress and whether its reading position is current. Thanks to @Kyraminol for the contribution (#763).
• The table view can now show a Tags column. In the redesigned interface's table view, each book's tags now appear as their own column, next to Series — handy when you're skimming or editing metadata and want to see genres and subjects at a glance. Use the "Columns" button to hide it if you'd rather not. Thanks to @mrdynamo and the original reporter (#725).

Fixed

• Russian interface translation updated with another round of corrections. Thanks to @standhaftsohnsergius (#740).
• Downloads failed with a server error for apps and scripts that don't send a browser identifier. Some OPDS readers, download managers, and command-line tools (curl, scripts) omit the User-Agent header. Those requests hit a 500 error instead of the book — the download and OPDS-download endpoints assumed the header was always present. They now handle its absence and serve the file normally. Thanks to @AshayK003, who reported and fixed the same crash upstream (janeczku/calibre-web#3668).
• The "duplicates found" notice no longer nags about books you've archived. If you archived one book of a duplicate pair, the duplicates page correctly showed nothing — but the sidebar badge and the pop-up notice kept counting it, so clicking through led to an empty page and the notice came back on every refresh. The count now respects the same archived and hidden books the duplicates page does, so the badge and the page agree. Reported by @auspex (#737).
• OPDS feeds now each show their own name instead of all reading as your library's name. In an OPDS reader, "Read Books," "Unread Books," each shelf, the author and series lists, and search results all appeared with the same title — your instance name — so the feed list was a wall of identical entries. Every feed now shows "Instance - Feed Name" (a shelf shows its own name, a search shows the query), so readers that list feeds by title can tell them apart. Thanks to @chloeroform for the report (#750).
• Parts of the new interface stayed in English even when your language was fully translated. Menu items like "Table view" and "Smart shelves," and whole screens such as the admin settings, cover picker, advanced search, and the book editor, showed English in the redesigned interface while the classic view translated them correctly. Those strings were never being collected for translation, so no locale could pick them up. They are now, so they translate into your language as each locale's translation is filled in. Thanks to @standhaftsohnsergius for the detailed report (#719).
• Author names with a comma (like "William H. Keith, Jr.") now show the comma, not a pipe. In the redesigned interface, an author whose name contains a comma appeared under book titles as "William H. Keith| Jr." — a raw | where the comma should be. Calibre stores those commas internally as a pipe, and the new interface was showing the stored form instead of the display form. Book cards on the Library and author pages, and the book detail page, now render the comma correctly. Reported on Discord by neontapir (#730).
• Automatic Hardcover matching finds the right book more often. When auto-fetching Hardcover metadata, the matcher only scored the first 10 of the up-to-50 results the search returns, so a correct edition ranked lower down (Hardcover puts author-in-title hits first) could be thrown away before it was ever considered. It now scores the whole result set, and the manual-review screen's "Top N" heading matches the candidates it actually shows. Thanks to @Schmavery for the fix (#729).

Changed

• Book lists load as you scroll instead of behind a "Load more" button. The Library grid, Table view, shelves, smart shelves, and advanced-search results now fetch and append the next page automatically as you near the bottom, so browsing a large library is one continuous scroll. Thanks to @kurtlieber for the contribution (#735).
• Reordering your sidebar sections now feels smooth and physical. In the Customize panel (the left rail's Customize control), dragging a section used to snap the other rows around with no sense of motion and could jitter or stick at row edges. Now the row you grab lifts and tracks your pointer while the others glide aside to open a gap, then it settles into its slot when you release — the same on mouse, touch, and pen. Keyboard reordering (focus a section's drag handle, then use the arrow keys) and hiding/restoring sections animate through the same motion, and everything falls back to instant when your system is set to reduce motion.

[v4.1.7] - 2026-07-08

Added

• Book pages now show star ratings and more from the same author. In the redesigned interface, a book's page now displays its star rating (matching the classic view), and — below the details — a "More by this author" row of other books by that author, so a book page is a place to keep browsing instead of a dead end. Books with no cover art or description no longer leave the page looking half-empty.

Fixed

• Admins can find the Admin page in the new interface again. In the redesigned UI the Admin/Settings entry lived only in the left sidebar rail, so admins who looked in the account (avatar) menu — the usual home for "Settings/Admin" — saw only My account, Back to the classic view and Sign out, and some switched back to the classic interface because they couldn't find admin. The account menu now shows an Admin link (for admin accounts only) that opens the in-app admin page. Reported through the in-app feedback form (#659).
• The bulk-edit toolbar no longer shows a raw code placeholder. In the new interface, selecting several books and choosing merge or bulk-apply showed literal text like "Merge %(n)s books…" and "Apply to %(n)s books" instead of the actual count. Both now read correctly (e.g. "Merge 3 books…"). The same underlying issue was corrected on the book page's tag controls.
• Downloading a book on an iPhone no longer strands you. In the new interface, tapping a format to download it used to navigate Safari away from the app to a page it couldn't show — leaving iPhone users stuck until they force-restarted the app to get back. Downloads now open in a separate tab, so the app stays put and you land right back where you were. Reported by @Arjan61 (#716). Also applies to the download buttons on the edit-book screen and the annotation exports.
• Russian translation corrected in the new interface. The font-setting labels in the redesigned UI were untranslated, and a few strings showed the wrong text (the "System Sans-Serif" font option read «Статистика системы»). Russian now reads correctly throughout those settings. Contributed by @standhaftsohnsergius (#718).
• Auto-adding metadata during import no longer skips the cover on some setups. On libraries that store book files separately from metadata.db (the "split library" option), fetching metadata during ingest failed to save the downloaded cover and logged an internal error. Covers now apply correctly during import. Reported by @maraken (#709).
• Marking a book "unread" now fully resets it. After opening a book "just to test it", marking it unread cleared the reading percentage but the book could stay flagged as Currently reading. Unread now clears that state too, so the book reads as untouched everywhere. Reported by @uschi1 (#683).
• Converting from formats that need a Calibre plugin works again. Converting e.g. KFX→EPUB failed with "No plugin to handle input format" even with the plugin installed, because the converter wasn't looking in your Calibre plugins folder. It now does. Reported by @jhazan-jpg (#724).
• Changing a book's cover now updates the cover inside the file. Picking a new cover updated it in the library but downloads (and the "Currently embedded" preview) kept the old image. The new cover is now embedded into the book file. Reported by @GustavPersson (#707).
• Removing a duplicate now tells your Kobo to drop the old copy. When the duplicate-scanner replaced an older copy of a book with a newer one, the server never told a synced Kobo that the old copy was gone, so it could linger as a duplicate. The server now sends the removal to the device on its next sync. (Some Kobo devices may still keep a removed sideloaded book until it's archived on the device — we're improving that in a follow-up.) Reported by @Chronosmage-alt (#708).
• Uploading a new format to a book no longer creates a duplicate on very long filenames. An over-long uploaded filename could be imported as a separate book instead of being added as a format to the existing one. Reported by @jrhedman (#690).

[v4.1.6] - 2026-07-07

Added

• Pick the right Hardcover edition when fetching metadata (new interface). On a Hardcover search result you can now click Editions to drill into that book's individual editions (paperback, e-book, translations…) and apply the one you want — so the correct edition ISBN and Hardcover edition id land on your book, which is what Hardcover reading-progress sync needs to match the right copy. Every result also gets a ⋯ (View all details) button that opens the full record — complete description, every tag, and each identifier on its own line — as a popup on desktop or a bottom sheet on mobile, so nothing is hidden behind the truncated preview. Requested on Discord (mgrimace, Wasabi).

• A "What's New" page, so you can see what changed without reading a changelog. The Help menu (the "?" in the top bar) now has a What's New entry that opens a plain-English log of recent features and fixes — newest first, grouped by release, each with a "Try it" link straight to the thing it describes. A small dot on the Help menu points it out once after an update and clears the moment you open it.

• Customize your sidebar from the new interface. A Customize capsule at the top of the left rail turns the sidebar into an editable list: drag sections into the order you want (for example, move Shelves to the top so you don't have to scroll) and tap the ✕ to hide the ones you don't use. Reordering works with the mouse, on touch, and with the keyboard, and your layout is saved to your account. Earlier (v4.1.4) the new UI started respecting the visibility settings from the classic interface; now you set both visibility and order without leaving the new UI. Requested by @Glennza1962 and @alva-seal (#585).

• Choose the interface font in the new UI. Account settings now has UI body font and UI display font pickers — pick System Sans-Serif, a bookish serif, or monospace instead of the defaults. Each option previews in its own font, the choice is saved to your account so it follows you across devices and browsers, and "Default" always returns to the theme font. Contributed by @kurtlieber (#701).

Changed

• New browser-tab icon that matches the app. The favicon is now the amber book mark from the refreshed interface, on the app's dark background — so the tab, bookmark, and home-screen icon read as Calibre-Web NextGen instead of the inherited upstream icon.

Fixed

• Removed the stray number next to "User administration" in the new interface. The admin page showed a bare, unlabeled count (e.g. "1") beside the title that read as a glitch rather than information. It's gone; the user count is already clear from the list itself. Reported by @chloeroform (#669), patch by @chloeroform.
• KOReader reading position now syncs between two devices even after a book is re-uploaded or edited. If one reader was ahead (say 80%) and the other behind (67%), the second device could refuse to jump forward — a manual pull just said "already synced". This happened when the two devices held slightly different files for the same book (a re-download after a metadata edit, a sideloaded copy, or a format the server didn't embed metadata into), so the server couldn't tell they were the same book and kept each device's position separate. The server now registers the fingerprint of every file it hands out (not only metadata-embedded downloads) and unifies a book's reading position across all of a book's known files, so the furthest position wins on every device. Reported by @Glalith121 (#633).
• Your profile picture now shows in the new interface. If you set a profile picture in the classic account settings, the new interface didn't use it — the account button in the top bar and the account page both showed a generic silhouette. Both now display your picture, and fall back to the silhouette only when you haven't set one. Reported by @chloeroform (#668).
• Marking a book "unread" now clears its reading progress. If you opened a book just to peek at it, it could stick at something like "0.6% read" with no way to reset it — the read/unread switch flipped the status but left the percentage behind. Marking a book unread now also resets its progress to zero (and clears where the in-browser reader would resume), so an unread book reads as untouched everywhere. Marking a book read is unchanged. Reported by @uschi1 (#683).
• The new interface now hides the smart shelves you turned off. If you unticked some entries under "Magic Shelves Visibility" in your account settings, the new UI sidebar still listed every smart shelf — the setting only worked in the classic view. The sidebar now honours it, so hidden smart shelves stay hidden in both interfaces. Reported by @chloeroform (#667).
• Fixed a startup crash-loop on servers that had synced annotations to Hardcover. If your library had ever synced highlights to Hardcover, an upgrade could get stuck restarting over and over, never finishing boot. A one-time database migration was refusing to run because it double-counted sync records the app had written during normal use. The migration now checks the right thing and completes, so the server starts normally again — no data is lost and no manual steps are needed. Reported by @PulsarFTW (#684).
• The "Currently reading" badge now shows on the new-UI book page. A book you're partway through on KOReader/Kobo showed the "Currently reading" marker on the classic book page but nothing on the new UI. The new-UI book page now displays the same marker — with the synced percentage when it's known — while unread and finished books still don't show it. Reported by @iroQuai (#634).
• Fetch Metadata no longer shows the same cover for every volume of a series. Searching for one volume of a series could return results where Vol.1, Vol.2, and Vol.3 all carried an identical cover — and applying metadata then saved that wrong cover onto the book. The cover-upgrade step now refuses to swap in artwork whose volume number disagrees with the book's title, and Kobo search results keep their ISBN so the exact-edition cover sources can be used in the first place. Reported by @boegill (#638).
• Your shelves are listed under the SHELVES heading in the sidebar again. In the new UI the sidebar showed a SHELVES heading with Tasks and About directly beneath it, while your actual shelves were pushed to the very bottom of the menu, off the end of the drawer. Shelves now appear right under the SHELVES heading, with Tasks and About moved to the bottom where they belong.
• The "Contribute here!" link on the translation banner works again. When your language is only partly translated, the banner offering to help now points at the wiki page that exists instead of a renamed one that returned a "page not found".

[v4.1.5] - 2026-07-03

Fixed

• "Currently Reading" now shows the right books for libraries that use a Calibre "Read" column. If your admin settings link read status to a custom Calibre column, the Currently Reading smart shelf listed every book you'd marked read and never the book you were actually partway through — and the "reading now" badge on a book's page never appeared, even with KOReader progress synced. In-progress state (which comes from KOReader and Kobo sync) is now read from the sync tracker regardless of the configured column, and finished books stay out of the shelf. "Yet to Read" also now counts books you've never touched, instead of only books explicitly marked unread. Reported by @alva-seal, seconded by @iroQuai.
• KOReader sync now works when your reader matches books by filename. KOReader's sync plugin (and apps like Crossink) can identify a book by a hash of its filename instead of its file contents. The server only ever knew the content hash, so filename-mode devices always got "no book found" and progress never linked up. The server now registers a filename digest for every book — on download and, for your existing library, automatically at startup. This also gives devices holding older copies of a book (from before an update, or side-loaded) a way back into sync without re-sending every file: switch the KOReader sync plugin's document-matching method to "filename". Reported by @natabat, seconded by @Metamatam; also relevant to reports from @uschi1 and @Glalith121.
• A single problem PDF can no longer hang the whole server on download. Downloading certain PDFs (UI or OPDS) triggered a metadata-embedding step that could hang inside Calibre's PDF writer, pinning a CPU core, eating memory, and leaving the request stuck until a 504. The embed step is now bounded (90 seconds by default, tunable with CWA_EMBED_TIMEOUT), the hung Calibre process tree is cleaned up, and the download falls back to serving the original file from your library — you get your book instead of a dead server. Send-to-eReader and Kepub conversion degrade the same way instead of failing. Reported by @darkmatterpelican.
• The library's view-settings (gear) menu no longer opens offscreen on phones. On narrow screens the toolbar wraps, and when the gear ended up on the left side its menu opened toward the left and slid off the edge of the screen. The menu now drops below the toolbar and stays fully visible at any width. Reported by @iroQuai.

[v4.1.4] - 2026-07-02

Added

• Quick-edit shortcuts are back in the new UI. Two things the old interface had returned: hovering a book in your library or search results now shows a small pencil that drops you straight into that book's edit page — no need to open the book first. And on a book's page you can now add or remove individual tags right there (each tag has an × to remove it, plus an "Add tag" box) rather than opening the full editor and hand-editing a long comma-separated list. Both only appear if you have edit permission. Larger batch-editing improvements are still on the way. Reported by @magdalar.
• The new UI's sidebar now respects which sections you've turned off. Just like the classic UI, if an admin (or a per-user setting) has hidden sections such as Hot, Top Rated, Discover, Categories, Series, Authors, Publishers, Languages, Ratings, Formats, Archived, Favorites, Table view, or Duplicates, those entries no longer appear in the new-UI sidebar — it follows your configured Visibility settings instead of always showing everything. Nothing changes if you never hid anything. Reordering sidebar entries is still on the list for a later update. Requested by @Glennza1962.

Fixed

• The new UI can now sort a series by its reading order, and shows each book's position. Opening a series in the new UI listed its books newest-first with no way to order them 1, 2, 3, and the series position never appeared on the covers unless you'd baked it into the titles. A series now opens in ascending series order by default, the sort menu gains "Series order" (and its reverse) while you're inside a series, and every cover shows its number. Reported by @magdalar.
• Admin config links now work behind a reverse proxy on a sub-path. In the new UI, the "More server configuration" cards on the Admin page (Basic configuration, Database & library path, Scheduled tasks, Logs, and the rest) pointed at the domain root instead of inside your mount, so on a setup served at something like https://host/cwa/ they broke out of the app and landed on a 404. They now stay inside the sub-path like the rest of the interface. Installs mounted at the domain root are unaffected. Reported by @chloeroform.
• Opening a "More server configuration" page no longer throws you out of the new UI. Those cards on the Admin page link to the deep, classic configuration screens (database path, scheduled tasks, logs, and the like). Clicking one used to replace the whole new interface with the old page, so it felt like the app had reverted to the old UI. They now open in a new browser tab, so the new UI stays exactly where it was and you can close the tab to come back. The full native rebuild of those config screens is still on the roadmap. Reported by @Glennza1962.
• The new UI now shows your site's name. If you set a custom title under Admin → Basic Configuration, the new UI ignored it — the top bar, the login screen, and the browser tab always said "Calibre-Web NextGen". All three now follow your configured title; installs that never changed the title look exactly the same as before. Reported by @Glennza1962, confirmed by @iroQuai.
• French (and 16 other languages) no longer offer "mark as unread" on a book you haven't read. The new UI's read toggle said "Marquer comme non lu" (mark as unread) on unread books because the translation for "Mark as read" carried the opposite meaning — the same copy-paste slip existed in Arabic, Czech, Greek, Spanish, Finnish, Galician, Indonesian, Portuguese, Slovak, Slovenian, Swedish, Turkish, Ukrainian, Vietnamese, and both Chinese variants. All 17 are fixed. The classic detail page's big read button also said "Lu" (has been read) in French where it meant "open the reader" — it now says "Lire", and the status badge keeps "Lu" where that's correct. Reported by @hayvan96.
• You can log out again on mobile in the classic view. With the caliBlur theme on a phone, tapping your username in the menu did nothing — an invisible upload control was swallowing the tap, so the account submenu with Logout never opened, and the drawer's profile area rendered squashed with overlapping text. The profile block now sits in its own space again and tapping your name reliably opens the menu. Reported by @iroQuai.
• Switching shelves no longer mixes both shelves' books. In the new UI, going from one shelf straight to another kept the first shelf's books on screen and drew the next shelf's books after them — and removing one of the leftover books actually removed it from the shelf you were now on. Each shelf (and smart shelf) now shows only its own books, and the page counter resets when you switch. Reported by @mstewart14.
• Table view covers are no longer squished. In the new UI's Table view, cover thumbnails rendered as narrow 32px slivers that cropped the sides off the artwork. They now display at a proper book-cover shape (48×72), and on desktop a title made of one long unbreakable string (common for auto-ingested filenames) wraps inside its cell instead of forcing the whole table to scroll sideways. Reported by @blahblah57.
• The library now keeps your scroll position when you scroll the first page and go Back from a book. The scroll-restore added in v4.1.1 worked once you'd loaded more pages, but if you only scrolled the first screen of books, opened one, and came back, the list jumped to the top. Reported by @KucharczykL.
• App passwords now work with the KOReader plugin. KOReader sync only accepted your main Calibre-Web password, so OAuth- or LDAP-only accounts (which have no local password) got "Invalid password" and a 401. KOReader progress and annotation sync now accept per-user app passwords, the same as OPDS already does. Reported by @alva-seal.

[v4.1.3] - 2026-07-01

Corrective release: if you're on v4.1.1 or v4.1.2, update — those versions show a stuck popup over the classic view.

Fixed

• The classic view no longer shows a feedback popup you can't close. In v4.1.1 and v4.1.2, the optional "what made you switch back?" prompt appeared on every classic page — not just after switching from the new UI — and none of its buttons could dismiss it (on phones it didn't even fit the screen). It now stays hidden unless you've just switched back from the new interface, every button closes it, and it fits and scrolls on small screens. Reported by @iroQuai (#576).

[v4.1.2] - 2026-07-01

This release carries exactly the same fixes as v4.1.1, re-published under a new version number so the in-app "update available" prompt reaches everyone. If you updated to v4.1.1 in the short window right after it first went out, you may have landed on an earlier build of it; moving to v4.1.2 guarantees you're on the corrected version. Nothing else changed — the full list of what's fixed is in the v4.1.1 notes below.

[v4.1.1] - 2026-07-01

Added

• The new-UI edit page can now edit identifiers, and you choose which fetched values to apply. Editing a book in the new interface now has an Identifiers table — add, change or remove ISBN, ASIN/Amazon, Google, DOI and the rest — and when you fetch metadata from the web, each result has a "Choose fields" checklist so you apply just the title, cover, description, identifiers (or whatever you pick) instead of overwriting everything. Reported by @uschi1 (#580).
• Switching back to the classic view now asks (optionally) what made you switch. The new interface's user menu has a "Back to the classic view" item; when you use it, the classic page shows a short, two-step prompt — pick what didn't work and add a note if you like. It's completely optional and anonymous: no account, name, IP address, version or device info is sent or stored (it's sent over HTTPS and saved as just your feedback, like unmarked mail). It only appears right after you switch back, and won't nag you again.

Fixed

• The new UI's book page now shows your KOReader/Kobo reading progress. If you sync progress from KOReader or a Kobo, the book page again shows "KOReader progress: X%" (it was only on the classic page before — the synced progress was never lost). Reported by @alva-seal (#587).
• Dutch: the new UI's book buttons read correctly. The button that opens the reader said "Gelezen" ("has been read") instead of a "read now" verb, and the already-read marker showed the English word "Read". The reader button now says "Nu lezen" and the marker shows "Gelezen ✓". (Under the hood the reader action and the read-status label are now separate strings, so this collision can't recur in other languages either.) Reported in #577.
• Book identifiers are clickable links again in the new UI. On a book's page, identifiers like Goodreads, StoryGraph, Hardcover, Amazon and ISBN now link out to the book on that site (as they did in the classic UI) instead of showing as plain text. Reported by @alva-seal (#582).
• The new UI now keeps your place in the library when you go back from a book. Scrolling down, opening a book, then pressing Back used to jump you to the top of the library (losing loaded pages) — annoying when opening several books in a row. It now restores your scroll position and the books you'd already loaded. Reported in #578.
• The mobile menu drawer in the new UI is now solid and scrolls properly. On phones, opening the navigation menu showed a see-through panel that couldn't be scrolled — trying to scroll it moved the page behind instead, so lower items (like Magic Shelves) were unreachable. The drawer now has a solid background and scrolls on its own. Reported in #576.
• The new UI now shows the Calibre-Web favicon in the browser tab. The redesigned interface had a blank tab icon; it now uses the same favicon as the classic UI (and it works behind a reverse-proxy subpath too). Reported in #574.
• The new UI now works behind a reverse proxy with a path prefix. If you serve Calibre-Web NextGen under a subpath (e.g. https://host/cwa/ via nginx, Traefik or similar), the new interface showed a blank white page because its scripts, styles, API calls, covers and downloads were requested without the prefix and 404'd. Everything now honours the mount prefix automatically, so the new UI loads and works the same behind a subpath as at the domain root. Reported by @chloeroform (#571).
• The read/unread checkmark shows again in the new UI when read status is linked to a Calibre column. If you set Admin → View Configuration → "Link Read/Unread Status to Calibre Column" to a custom column, the new interface showed every book as unread (no checkmark) and the read/unread filters returned everything. The new UI now reads that column, so finished books get their badge and the Read/Unread/Discover filters work again. The built-in read status is unchanged. Reported by @uschi1 (#579).

[v4.1.0] - 2026-06-30

Changed

• The new interface is now offered to everyone — opt in when you're ready. After updating, a dismissible bar invites you to try the redesigned interface; your classic view stays the default until you tap "Try the new UI" (or the "Switch to New UI" button in the top bar). Dismiss it and it stays gone until the next update, when it gently reminds you again. You can still turn the new interface off entirely by setting CWNG_SPA=0. (Previously the new UI was hidden unless an admin opted the whole instance in.)

Added

• A redesigned "Change cover" screen in the new UI. Picking a new cover now opens a polished page instead of the old one: your current cover with a one-tap lock (so a metadata refresh can't overwrite it), a grid of candidates from every source we search (plus the cover embedded in the book), and tabs to paste a URL or upload your own. If you use a Kobo, flip on E-reader preview to see how each candidate looks padded for your device before you choose. You can reach it straight from a book — hover or tap its cover and choose Change cover — or from the edit page. Keyboard- and screen-reader-friendly throughout.
• A "Discover" shelf of random picks on your library home (new UI). The redesigned library now opens with a set-apart "Discover" box — a row of random books from your collection to stumble onto something to read. Hit the shuffle button for a fresh set, dismiss it with the × in its corner, and bring it back any time from the new gear (View settings → "Show Discover section"). Your choice is remembered on that device.
• "Remember me" and a show-password toggle are back on the new sign-in screen. The redesigned login page now has the "Remember me" checkbox (on by default, so you stay signed in) and an eye button to reveal what you typed — matching the classic login.
• Magic-link sign-in now has a polished page in the new UI. Choosing "Log in with a magic link" opens a redesigned screen with the QR code, a one-tap copy of the verification link, a live "waiting…" indicator and an expiry countdown. Scan or open it on a device you're already signed in on and the waiting device logs in automatically. (Previously this dropped you onto the old-style page.)
• The version number on the Admin page links to its release notes. The "Calibre-Web NextGen" version in the Version Information table (Admin page) is now a link to that release's notes on GitHub, so you can see what changed in the build you're running. Dev/canary builds link to the releases list instead. Requested by @chloeroform.
• Email your users straight from the admin area. A new "Email Your Users" page (Admin → Email Your Users) lets you write a message and send it by email to everyone — or just the people you pick. Handy for announcing new books or server updates to the people sharing your library. It uses the same mail server you already set up for password resets, formats with HTML (links, bold) with an automatic plain-text fallback, can pull in your announcement banner text with one click, and has a "Send test to me" button so you can preview before sending. Messages send in the background — check Tasks for delivery. Requested by @froggybottomboys.

Fixed

• Uploading a book with a very long filename no longer fails. A file whose name ran past the filesystem limit (~255 characters) used to fail to import with an unhelpful "Failed to queue for processing" message. The temporary staging name is now trimmed to fit (the file is renamed from its metadata on import anyway), so the upload succeeds. Normal filenames are untouched. Reported by @chloeroform (#553).
• Bulk actions and drag-to-merge now work behind a reverse proxy on a sub-path. If you run NextGen under a proxy mounted at something like example.com/books/, marking books read/unread, adding a selection to a shelf, deleting selected books, the cover badge toggle, and dragging one book onto another to merge all failed with a 404 — those requests went to the server root instead of your sub-path. They now use the correct path in every setup. Nothing changes if you don't use a sub-path proxy. Reported by @chloeroform.
• The "Discover (Random Books)" row now actually appears. Turning on "Show Random Books in Detail View" did nothing — a leftover theme rule hid the random-books row for everyone, so the "No. of Random Books to Display" setting had no visible effect. The row now shows as a "Discover (Random Books)" strip above your book list, on desktop and mobile. Reported by @chloeroform.
• Changing the "Regular Expression for Title Sorting" now re-sorts your whole library right away. After editing that setting (Admin → UI Configuration), the book order didn't change until you edited each book one by one — the new rule only applied to books you touched afterwards. Saving the setting now recomputes the sort order for every book immediately, the same way Calibre desktop does. Reported by @chloeroform.

[v4.0.172] - 2026-06-25

Added

• Books you're partway through now show a "Currently reading" badge. If you read on KOReader (or a Kobo) and your progress syncs back, the book used to look exactly like one you'd never opened — the web only marked books as read once you finished them. Now an in-progress book gets an amber "Currently reading" marker on its detail page and a badge on its cover in the grid, shelves, search and author pages, so synced reading progress is actually visible. Reported by @barukh27.

Fixed

• Sorting the Books List by Title no longer breaks the table. In the "Books List" table view, clicking the Title, Title Sort, or Series ID column header produced an empty table and flooded the log with no such column: title errors — only Author sorting worked. The table now sorts correctly by every column. Reported by @Mr-Me-torn.

[v4.0.171] - 2026-06-24

Added

• Choose what permissions new Generic OAuth users get. Instead of every OAuth sign-up inheriting the one global default role, admins can now set a per-provider permission set (downloads, viewer, uploads, edit, delete, change password, edit public shelves) for accounts auto-created via Generic OAuth. Leaving it unconfigured keeps the existing global default, so upgrading changes nothing until you opt in. Existing users are untouched. Thanks to @lduesing.
• Restrict Generic OAuth/OIDC login to specific identity-provider groups. Admins can now require that a user belong to one of an allowed list of OAuth groups before an account is created or logged in, and can name the token claim that carries the group list (handy for Keycloak/Authentik, which often use a custom claim rather than groups). Membership is enforced before any account is provisioned, and turning the requirement on with an empty allow-list denies everyone rather than admitting all directory users. Thanks to @lduesing.

Fixed

• "Send to eReader" now shows the real reason it failed. When your mail server rejected the recipient address, the send used to die with a confusing TypeError and hid the actual rejection. It now reports the address and the server's reason (e.g. kid@home.net: 550 User unknown) so you can fix it. Reported by @kurtlieber.
• Beta (:dev) builds no longer nag about a "false" update. If you run the beta image, the "update available" banner kept pointing at the latest stable release even though a beta build is actually ahead of it. Beta/unversioned builds are now recognised and don't show the banner.
• Stacked notices no longer pile up into an unreadable blur. When more than one pop-up notice showed at once — e.g. the duplicate-scan setup notice plus the update banner — they all floated to the same spot and rendered on top of each other. They now stack neatly in a column.

[v4.0.170] - 2026-06-23

Added

• Update from a button instead of hunting for the right Docker command. When a new version is available, the update banner and the Admin page now show an Update now button that gives you the exact one-line command for your setup — Docker Compose, docker run, Unraid, or Portainer/Synology — with one-click copy. A new Automatic updates section under Admin → NextGen Settings walks you through turning on truly hands-off updates with Watchtower, so new versions install themselves. (Admin only.) The README gains a matching "Updating" guide, including how to run NextGen under Podman.

Fixed

• The epub reader's Settings panel no longer sits flush against its edges. After the recent settings redesign, the option labels were pressed against the left edge and the slider readouts ("150%", "0px") were clipped at the right. The panel now insets its content again, and the "Settings" title keeps its full-width bar across the top. Reported by @sambong.
• The Duplicate Books page works again behind a reverse proxy on a sub-path. Behind a proxy mounted on a sub-path, the cover placeholder kept requesting generic_cover.svg in an endless loop, and dismissing or resolving a duplicate group failed with "Failed to update duplicate group." Both came from page URLs that dropped the proxy's sub-path prefix; they now carry it. Reported by @chloeroform.

[v4.0.169] - 2026-06-22

Changed

• Simplified Chinese (zh_Hans): more of the interface now appears in Chinese — 279 menu, button and message strings that previously fell back to English are translated. Thanks to @GSAlex.
• Spanish (es): 76 strings that were showing in English — or, in a few cases, the wrong Spanish phrase — now read correctly. This covers the duplicate-book tools, OAuth sign-in messages and several admin labels. Thanks to @HaruIjima-kun.

Fixed

• Kobo no longer re-downloads your whole magic shelf on every sync. If you synced magic (smart) shelves to a Kobo, books kept dropping back to "Download"/"Unread" and losing your place — every sync unless you synced twice back-to-back. The shelf's membership cache was being re-stamped with a new timestamp every 30 minutes even when nothing changed, which made the sync re-send the entire shelf. It now only re-sends when the shelf's contents actually change. Reported by @Glennza1962 and @bigbold1023.
• Right-click on an image in the epub reader now offers "Save image as" again. The reader was swallowing the right-click (and Android long-press) menu on everything so the in-app highlight popup could be the way you select text — but that also blocked the browser's own menu on illustrations, so you couldn't save a picture. Images now get their native menu back (including the iOS long-press "Save Image"), while right-clicking text still opens the highlight popup. Reported by @sambong.
• The epub reader's Settings panel no longer gets cut off on short browser windows. On a window shorter than the panel — common on a NAS admin tab — the Theme row at the top and the Font, Spread and Reflow options at the bottom were clipped off-screen with no way to scroll to them. The panel now caps its height and scrolls internally at every window size, so every setting stays reachable. Reported by @sambong.

[v4.0.168] - 2026-06-19

Fixed

• Archiving a book now updates the shelf count in the sidebar. The badge next to a shelf name counted archived books even though opening the shelf already hid them, so the number stayed too high. It now matches what you see inside the shelf. Reported by @jasonxbergman.

[v4.0.167] - 2026-06-18

Added

• You can now support Calibre-Web NextGen's development directly — the project has its own Ko-fi, linked from the README and the GitHub "Sponsor" button. (The upstream project it builds on is still credited and linked too.)

Fixed

• Hardcover metadata search no longer fails when one of your saved API tokens is stale. If you have both a per-account token and a global one, search used the per-account token and gave up if it was expired — even when the global token was valid. It now tries each configured token until one is accepted, and trims a stray Bearer prefix or whitespace from a pasted token. Thanks to @WasabiBurns for diagnosing the precedence.
• On a Kobo that syncs by shelves, a book you're currently reading no longer gets removed from the device and forced to re-download because of a momentary database hiccup while the server works out which books belong on your sync shelves. If it can't read that list reliably, the sync now leaves your books in place and reconciles on the next sync, instead of treating the failure as "this shelf is empty." Reported by @Glennza1962 and @bigbold1023.

[v4.0.166] - 2026-06-17

Added

• The KOReader sync plugin can now be kept up to date with the Updates Manager plugin (updatesmanager.koplugin) instead of hand-copying files onto your device. The plugin now reports its version where Updates Manager looks for it, and every release ships a ready-to-install cwasync.koplugin.zip on the GitHub release page — extract it into KOReader's plugins folder, or point Updates Manager at this repository to install updates from the KOReader menu. Requested by @filiporlo.
• Tap the left or right side of the page to turn pages in the web reader. The page is split down the middle — tap (or click) the right half to go forward, the left half to go back. Swiping left/right still works. Two annoyances are fixed along the way: a stray finger-wobble no longer flips the page, and selecting text to highlight no longer turns the page out from under you.
• Your reader display settings now follow you across devices. Theme, font, font size, page layout and the new text-margin setting are saved to your account, so a book you open on your phone looks the way you set it on your laptop — previously these lived only in one browser and didn't travel.
• Adjustable text margins in the reader. A new slider in the reader's Settings trims the side whitespace to fit more text per line, or widens it — whatever's comfortable to read.
• You can now star your favorite books. Tap the star on a book's page — or the star on its cover anywhere in the grid — to favorite it; favorited books show a gold star on the cover. Use the new Favorites entry in the sidebar to see just your starred books. Favorites are private to your own account.
• The Published Date field now accepts just a year. When you edit a book you can type 2020 (or 2020-05) instead of clicking through the date picker for the full day — the missing month and day default to January 1st. Handy for the many books that only carry a publication year. Thanks to @huperaisan for the suggestion.

Changed

• On the main books list, your starred books now float to the top, so your favorites are the first thing you see in the full library (the Favorites sidebar entry still shows them on their own). Within the starred group your chosen sort order still applies. Only the main list is affected — author, series, category and search views keep their usual order.
• Duplicate detection catches more real duplicates. Books that differ only by accents (Café vs Cafe) or punctuation (The Book! vs The Book) are now recognized as the same. It stays deliberately careful not to merge genuinely different books — "Dune" vs "Dune: Messiah" and "Volume 1" vs "Volume 2" stay separate — so nothing distinct gets wrongly flagged for removal.
• The Magic Shelf editor is easier to use on a phone. The rule builder and the Kobo-sync / OPDS / public option cards were being squeezed into a narrow strip with big wasted margins; they now use much more of the screen width, and each rule's field/operator/value controls stack full-width instead of clustering. A typo that mis-sized the rule's field dropdown is fixed too (helps desktop).
• In the web reader, long-pressing or right-clicking text no longer pops up the browser's own menu competing with the highlight popup — the in-app highlight menu is the one that shows. (On iOS Safari, Apple's built-in text-selection menu still appears alongside it; that one can't be switched off from a web page.)
• The reader's Settings panel has a cleaner layout — clearly labelled sections, live value readouts on the font-size and margin sliders, and bigger touch targets that fit comfortably on a phone.
• The book details page is easier to read, especially on phones. The big empty margins that boxed in the cover and info are gone — you get noticeably more width for the title, tags and description — and the page is tidier overall. The star rating now shows clean stars instead of a stray white box. On wider screens the cover and details sit side-by-side from 1024px up (previously only above 1400px), so desktops and landscape tablets use the width instead of stranding the cover alone in the middle.
• The book details page now has a clear Read button right under the cover — the full width of the cover — as the obvious way to start reading in your browser. The small "read" icon was removed from the row of action buttons so that row is less cluttered.

Fixed

• Books that a download client adds by hardlink into a subfolder of the ingest directory are now picked up automatically. Apps like Readarr and Bookshelf (via qBittorrent) hardlink completed downloads into per-author subfolders; a hardlink fires only a "create" filesystem event, never the "close-write" the ingest watcher waited for, so those books were silently skipped until you moved them to the ingest root by hand. The watcher now also acts on a completed hardlink (a file that already has its full contents), while still leaving an in-progress download to finish writing before it is ingested. Reported by @stuhby.
• A book you're in the middle of reading no longer disappears from the "Currently Reading" shelf just because it has no language set. If you've picked a preferred language in your account, the shelf used to silently hide any in-progress book missing language metadata — which often hit PDFs while EPUBs (which usually carry a language) stayed visible, even though the book's own page still showed your reading progress. The progress shelves now ignore the language preference, so everything you're actually reading shows up. Your other library filters (hidden, archived, tag restrictions) are unaffected. Thanks to @chloeroform for the report.
• On a phone, tapping the Search box (or other text fields) no longer zooms the page in. iOS Safari zooms toward any field whose text is smaller than 16px; the inputs are now sized so that doesn't happen, while pinch-to-zoom still works normally.
• The cover editor's Back link now returns you to wherever you opened it from — the book's page when you tapped its cover, or the edit screen when you came from there — instead of always jumping to the edit screen. The Edit metadata screen also gained a clear Back to book link at the top, and on a phone its form is no longer pushed off-screen.
• On a phone, the Edit Metadata page now shows the book's details form first — you can edit the title, author and tags straight away instead of scrolling past the cover. On wider screens the cover and form still sit side-by-side. (Builds on the earlier off-screen-form fix; replaces a brittle fixed-offset layout.)

[v4.0.165] - 2026-06-16

Fixed

• On a desktop browser, the Fetch Metadata popup on the Edit Book page no longer runs off the bottom of the screen when a search returns a long list of results — the "Close" button at the bottom stays on screen. Previously the popup grew taller than the window and the only way to dismiss it was the small "X" in the corner; zooming the page out to 80% was the usual workaround. Reported by @sltvtr.

Changed

• The Custom CSS and server announcement banner options moved to the UI Configuration admin page. They were previously on Basic Configuration, tucked inside the "Logfile Configuration" section next to the log level — an unintuitive spot that also disagreed with the documentation. They now sit in their own "Site Customization" section on the UI Configuration page. Existing values are preserved; nothing about how custom CSS or the banner behaves has changed, only where you set them. Reported by @Andrew-H2O.

[v4.0.164] - 2026-06-15

Fixed

• Editing a book whose author shares a name with another author after accents are stripped (for example "George Pólya" alongside "George Polya", or two Chinese names that romanize the same way) no longer fails with a database error. Previously any metadata change to such a book — even just adding a cover — was rejected. Reported on Calibre-Web by @annProg, @apetresc and @wnmurphy.
• On the caliBlur theme, the read-status quick-action button that appears when you hover a book cover now shows the right icon and tooltip the moment a page loads. In book lists like Read Books, search results and author pages, an already-read book used to show "Mark As Read" until you clicked it once; it now correctly shows "Mark As Unread" straight away. (Reported by @droM4X on #319)

[v4.0.163] - 2026-06-14

Fixed

• French (fr): the Hardcover integration labels no longer translate the service name "Hardcover" as "livres reliés" (hardback books). "Run Hardcover Auto-Fetch", "Hardcover Token Required" and "Enable Hardcover Auto-Fetch" now keep the Hardcover name so the buttons match the feature. Thanks to @Korri.
• Spanish (es): the "Invalid request" error now reads "Petición inválida" instead of the incorrect "Rol inválido" (Invalid role), and punctuation is tidied across 36 shared interface strings to match the source text. Thanks to @pablo-alcaniz.
• German (de): fixed 11 interface strings that showed the wrong text — the cover-size limit read "5-120 Minuten" (minutes) instead of "1–200 MB", "Failed to update shelves" showed the tags message, and "KOReader Sync is disabled" showed the default-login message. OIDC, logfile, email and Magic Shelves labels are corrected too. Thanks to @futurelook.

[v4.0.162] - 2026-06-13

Added

• You can now write your own message for the emails the server sends with a book. Edit Email Server Settings has a new "Email Message Body" box; whatever you type there replaces the default "This Email has been sent via Calibre-Web NextGen." on books sent to an eReader and on test emails. Write it in any language, add a link to your library, keep it short — leave the box blank to keep the original wording. (Requested by @iroQuai in #428)
• Admins can now style their instance with their own CSS. A new Custom CSS box under Admin → Edit UI Configuration injects your rules into every page as the last stylesheet, so they override the built-in themes — recolor the navbar, tweak spacing, adjust for your screen, all without editing source, and it survives upgrades because it lives in the database. The box is admin-only and can't accidentally break the page layout. (Issue #323 by @olskar)
• Magic Shelves can now filter on your Calibre custom columns. The rule builder lists every queryable custom column — text, numbers, yes/no, dates, ratings, and fixed-choice columns (which get a proper dropdown of their allowed values) — so shelves like "Mood is cozy" or "Page Count over 400" just work, including the "is empty / is not empty" operators. (PR #387 by @8bitgentleman)
• You can now open the same library in Calibre desktop while the server is running. Set NETWORK_SHARE_MODE=true plus the new DESKTOP_COMPAT_MODE=true and the server releases its database lock between web requests, so Calibre desktop opens the library instead of crashing or hanging; edits you make there show up in the web UI on the next page load. Occasional desktop use is the intent — heavy simultaneous use of both slows the web UI rather than corrupting anything. See the README's "Calibre desktop coexistence" section for trade-offs. (PR #386 by @8bitgentleman)

Changed

• Loading spinners are crisp at any size and follow your theme's color. The old animated GIFs (admin Restart/Status dialogs, settings save flashes, the book reader, and the PDF viewer) rendered pixelated and ignored your theme; they're replaced by a smooth CSS ring that matches the theme's primary color, centers correctly everywhere, and slows down rather than freezing when your system asks for reduced motion. (PR #384 by @jbelascoain)

Fixed

• The hover button for marking a book read/unread in the library grid now uses the same checkbox icons as the book page, instead of an eye symbol that looked like a hide/show control. The icon also tells you what the click will do — checkbox for "mark as read", unchecked box for "mark as unread" — and updates after each click. (#319 follow-up, reported by @droM4X)
• Turning on DEBUG logging no longer fills docker logs with repeating Magic Shelf messages. The "Found N total magic shelves", per-shelf "Hiding...", and "Filtered to N visible" lines fired on every request — an open browser tab meant the same block every ~3 seconds. They're now a single line that only appears when your shelf setup actually changes, with the hidden shelves named in it. (Fix by @KucharczykL in #443; reported by @SpookyUSAF in #445 and on CWA as #1060)
• Hardcover progress sync now survives Hardcover deleting or merging a book. If your book's saved Hardcover ID no longer exists ("We weren't able to find that book. Was it deleted?" in the logs), the sync looks up the book's current ID from its edition or slug and retries instead of giving up. When nothing can be looked up, the log now tells you the fix (refresh the book's metadata) instead of only the raw API error. (Follow-up to #433, reported by @SpookyUSAF)
• Calibre plugin and configuration loading is now reliable when you opt in with CWA_CALIBRE_USER_PLUGINS=true. The image used to set a misspelled environment variable (CALIBRE_CONFIG_DIR) that Calibre simply ignores, so Calibre invocations could fall back to a nonexistent home directory and miss plugins installed under /config/.config/calibre/plugins. The opt-in now sets Calibre's documented CALIBRE_CONFIG_DIRECTORY on every Calibre subprocess it covers (ingest, conversion, cover enforcement, metadata embed). Plugin loading stays off unless you opt in. (Diagnosed by @jasonobrien in #434)
• LubimyCzytac.pl metadata search returned "no results" for every book. The Polish catalog redesigned its site, so the provider's search and book-page parsing no longer matched anything — searches came back empty even though the site was reachable. Search now finds books again, and publisher, description, language, rating and publication date populate correctly on the metadata screen. Reported by @sltvtr (#431).
• Dropping an Adobe .acsm file into the ingest folder now explains what actually went wrong. An .acsm is a download ticket, not a book, so conversion fails — but the log only showed Calibre's cryptic "No plugin to handle input format: acsm" (followed by a stray "None"). The ingest log now spells out the two ways forward: install the ACSM Input plugin via CWA_CALIBRE_USER_PLUGINS, or fulfill the ticket in Adobe Digital Editions or Calibre desktop and ingest the downloaded book. Failure mode surfaced by @jbelascoain in #388 (#448).

[v4.0.161] - 2026-06-12

Fixed

• Hardcover progress sync no longer dies on books without a chosen edition. Reading on a KOReader/Kobo device synced progress to the library fine, but the push to Hardcover failed every time with 'NoneType' object has no attribute 'get' — typically when the book's entry on Hardcover has no edition picked, or when Hardcover rejects a status change. The sync now handles those responses, logs Hardcover-side errors with a full traceback, and tells you when a book needs an edition selected on Hardcover for page-based progress. (#433, reported by @SpookyUSAF)
• Search now opens on phones. Tapping the search icon in the top bar did nothing on mobile (most visibly in Safari on iOS) — the icon was covered by the header bar, so the tap never reached the search box, and the box never appeared. Tapping the icon now opens the search field as expected. Desktop is unchanged. (#425, reported by @getthething)
• On phones, the book detail page no longer shows an oversized, off-center cover. The cover used to render wider than its column and sit left of center (on the caliBlur theme), pushing the description far down the page. It now caps to its column and centers, and the title/spacing on narrow screens are tightened so the description sits closer to the top. (#288, reported with a screenshot by @iroQuai)

[v4.0.160] - 2026-06-10

Security

• Closed a cross-site scripting hole in the comic (CBR/CBZ) reader. The reader ran your saved page bookmark through JavaScript's eval(), so a bookmark value that contained code — which any logged-in account could store for a comic — would execute when the reader page opened. Bookmarks are now read strictly as a page number.

Fixed

• The metadata search dialog now lists providers in the order you set under Settings, instead of alphabetically. Whatever provider order you configure for automatic metadata fetching is now also the order the search popup shows and ranks results in, so your preferred source appears first.
• Adding several books at once to a Kobo-synced shelf now syncs them to Hardcover, just like adding one book does. Before, only single adds reached Hardcover — "add all" from search results, multi-select adds, and add-series-to-shelf silently skipped it. The sync now runs as a background task (visible under Tasks, cancellable), so adding a long series doesn't hold the page open on an external service — and single adds respond faster for the same reason.
• The experimental "SQL" duplicate-scan mode no longer produces different (and sometimes wrong) results than the default mode. It grouped co-authored books into multiple duplicate groups at once and skipped a title normalization the default scan applies, so the same library showed different duplicates depending on an admin toggle. That mode now uses the same single grouping engine as everything else, keeping SQL only as the fast candidate prefilter.
• Books you've hidden no longer show up in your duplicate scan. The Duplicates page respected your language, tag, and archive filters but not your hidden list, so hidden books reappeared there and could even be swept into duplicate auto-resolution.
• Duplicate detection now catches copies whose titles differ only in unicode form or spacing. A "Café" imported from a Mac (decomposed accents) and a "Café" typed by hand, or "The Book" with a double space, counted as different books and never showed up as duplicates. All duplicate matching now normalizes accents and whitespace first; the duplicate index rebuilds itself on first scan after the update, and your existing dismissals carry over automatically.
• Dismissed duplicate groups stay dismissed. Adding another copy of a book or editing its title changed the group's internal label, so groups you had dismissed popped back onto the Duplicates page (and could re-enter auto-resolve). Dismissals are now tied to the group's stable identity and survive new ingests and metadata edits; existing dismissals are upgraded automatically the first time they match. Two different groups that happened to share a display title also no longer share one dismissal.
• Merging duplicate books can no longer overwrite one of the kept book's files. If a file with the merge target's name was already on disk (from an earlier partial failure or a manual edit), the merge silently copied over it; it now refuses that group with a clear error and leaves every file untouched. A merge that fails partway also cleans up after itself instead of leaving stray copied files or phantom format entries behind.
• Finishing a book in KOReader now marks it read on the website when you use a custom "read" column. If your admin set a Calibre custom column as the read marker (a stock option under Feature Configuration), KOReader completions only wrote the built-in read list, so the book page checkmark stayed empty. The sync now also sets the custom column — and only ever sets it: re-opening a finished book never silently un-reads it.
• Automatic metadata fetch now actually downloads covers. The "update cover" option existed but did nothing — books imported with auto-fetch on never got their cover updated. Covers now download through the same safe path as the manual editor (size limits, image checks, server-side request protections), respect the per-book cover lock, and in "smart application" mode only fill in a missing cover, never replace one you have. (#404, confirmed by @beanscg)
• Downloading a cover by URL (manual editor and auto-fetch alike) no longer destroys the existing cover when the server misbehaves: a redirect stub or an error page served with an image content-type used to get saved as the cover file. The download now follows redirects properly (cover CDNs like Open Library's redirect every image) and verifies the bytes are really an image before anything is overwritten.
• Shelf reorder: the giant white sort icon (a down arrow with lines) that sat on top of the first covers on wide screens is gone. It was a leftover decoration from the old list-style reorder page — the theme drew it in what used to be empty space, and the new cover grid now fills that space. The wider your browser window, the bigger the icon got. (#320, reported with screenshots by @SpookyUSAF — the covers themselves were already the right size; this was the last piece.)
• Resolving duplicate books no longer loses your highlights, notes, reading progress, or shelf placement. When duplicates were merged or resolved, only the book files moved to the kept copy — anything you'd done on the removed copy (annotations, read status, Kobo reading position, shelf membership) silently disappeared. All of it now follows the kept book, whichever resolve strategy you use. Deleting a book and deleting a user also clean up everything that belongs to them now (deleted accounts previously left their annotations and annotation-backup files behind).
• Deleting a book no longer risks leaving a broken "ghost" entry if something fails partway through. Previously the book's files were removed before the library database was updated, so an error in between could leave an entry that still shows in your library but won't open. The database is now updated first and the files removed last, so a failure leaves the book fully intact. (Mirrors the same data-safety fix already made for duplicate resolution.)
• Shelf reorder covers: the stylesheet that keeps the covers at the normal thumbnail size now loads from the page head, alongside every other stylesheet, instead of from the page body. A body-loaded stylesheet link can be dropped by some reverse proxies, which left the covers oversized on an otherwise-correct page — the case @SpookyUSAF kept hitting on caliBlur even after v4.0.158/159. (#320 follow-up, reported by @SpookyUSAF)
• Automatic metadata fetch (the admin "auto metadata fetch" option, off by default) no longer overwrites a book's correct author, ISBN, series, publication date or rating with a wrong match's. Previously, with auto-fetch on, importing a book could silently replace good metadata with a random foreign edition's — and the "smart application" mode that's meant to only fill gaps didn't actually protect those fields. Now it prefers the edition whose ISBN matches your book, and smart mode never overwrites a value you already have (it only fills what's missing). Open Library is also now part of the default provider order.

[v4.0.159] – 2026-06-09

Added

• You can now add books to a shelf right from the shelf page. A new Add Books button opens a searchable picker — type to find books in your library, tick the ones you want, and add them all at once. Books already on the shelf show as "Already on this shelf" so you can't add duplicates, and it works on phone and desktop. Especially handy for filling a brand-new empty shelf.

Fixed

• Resolving duplicate books no longer risks leaving a book in a broken, half-deleted state if something fails partway through. Previously the files were removed before the library database was updated, so an error in between could leave a "ghost" book that still showed in your library but wouldn't open. The database is now updated first and the files removed last, so a failure leaves the book fully intact and the duplicate is simply re-resolved next time.
• Resolving duplicate books is now safe even if a duplicate scan happens to run at the same moment. Before, the two could collide — deleting the same book twice, leaving a duplicate only half-removed, or throwing a brief error that left the library inconsistent. Now only one resolution runs at a time and the other steps aside, so your books stay intact.
• Duplicate detection no longer treats books that are missing a title or author as duplicates of each other. Two unrelated books that both happen to have no title (or no author) used to collapse together as a "duplicate" — and could then be offered up for deletion. They're now kept separate; only books with real matching metadata are grouped.
• Resolving duplicate books is more reliable: the resolver no longer closes a shared database connection mid-operation, which could cause errors or a half-finished cleanup when the library was being used at the same time.
• The shelf reorder screen's cover-size fix now reaches more setups: the covers were still showing oversized for some users on v4.0.158 (e.g. behind certain reverse proxies). The styling moved out of the page into a regular stylesheet and now sizes covers on its own, so they stay at the normal thumbnail size regardless of theme or proxy. (#320 follow-up, reported by @SpookyUSAF)
• On phones, the menu (hamburger) button is now on the left, the same side the navigation drawer slides out from — so the button and the menu it opens line up. Tapping it opens the menu; tapping outside still closes it.
• On phones, the select and settings buttons above a book list now sit on the right (matching the desktop layout), so tapping the gear opens its menu on screen instead of off the left edge where it was getting cut off.
• Pages no longer occasionally fall back to the old, deprecated light theme — including error pages. That fallback could happen when a request hit a snag while loading, and it was the underlying cause of display glitches like the oversized shelf-reorder covers (#320). The dark theme is now enforced even on error pages and requests that are interrupted before they finish loading.

[v4.0.158] – 2026-06-08

Fixed

• The shelf reorder screen now shows covers at the normal thumbnail size instead of blown-up "large icon" size, and the Back button lines up under the covers with proper spacing above it. (#320 follow-up, reported by @droM4X and @SpookyUSAF)

[v4.0.157] – 2026-06-07

Added

• You can now add a whole series to a shelf in one click: series pages have an "Add Series to Shelf" button that adds every book in series order, skipping ones already on the shelf. (#334, requested by @Glennza1962)
• The book detail and edit pages now show the filename a book was imported with ("Imported as: …"). Ingest renames files to match their metadata — including wrong auto-matches — so the original name is the one stable reference for recognizing misidentified books while you fix their tags. Captured automatically for new imports from this version on. (#346, requested by @BakaPhoenix and @magdalar)

Changed

• Rearranging a shelf now happens in the same cover grid as the regular shelf view — drag a cover where it belongs, on desktop or phone (long-press to lift), or move it with the keyboard arrows. The order saves by itself on every change; the old cramped list and its Save button are gone. A shelf that changed in another tab no longer breaks saving. (#320, requested by @SpookyUSAF with design input from @droM4X)
• Series pages now list books in series order by default (1, 2, 3…) instead of newest-first — matching what the OPDS feed always did. Choosing a different sort still sticks for next time.
• On phones, the menu button now looks like one: a standard hamburger icon replaces the round profile-head glyph, which nobody recognized as the way to open the sidebar. Same spot (top right), same tap target; your profile options are inside the menu it opens, where they always were.

Fixed

• On phones, opening the sidebar no longer dead-ends the page: tapping anywhere outside the menu now closes it (it used to do nothing, and the menu button itself became untappable behind the overlay — the page was stuck until a reload).
• Fixed a rare freeze where the whole app could lock up — pages never loading until the container was restarted — when a background task (thumbnail generation, metadata backup, duplicate scan…) hit the database at the same moment as a page load. Database access is now coordinated so the standoff can't happen.
• Kobo sync no longer fails behind reverse proxies with default buffer sizes (Synology DSM, stock nginx). The sync token header could exceed nginx's 4K default when Kobo store proxying was on; it's now compressed to roughly half the size, with older tokens still accepted — no device reconfiguration needed. If you added proxy_buffer_size overrides for this, they can stay (harmless) or go. (#331, reported by @Gusdezup)
• "Reload Metadata" now also reloads authors, tags, and series (with series number) from the book file — previously only title, description, publisher, publish date, and languages came through. Author changes also rename the book's folder and file to match, the same way editing in the web UI does. A file that's missing its author or tags fields leaves your existing data alone instead of wiping it. (#218, reported by @yodatak)
• Adding a single book to a Kobo-synced shelf without JavaScript now syncs it to Hardcover the same way the normal button does.
• Bulk shelf adds no longer claim books were added when a database error actually rolled everything back.

[v4.0.156] – 2026-06-06

Fixed

• Magic Shelves marked for Kobo sync now actually reach your Kobo — books deliver and the shelf appears as a collection on the device. Previously a global setting (off by default) silently swallowed the per-shelf "Enable Kobo sync" checkbox; if you'd ever ticked that checkbox, the upgrade enables the global setting for you automatically. The checkbox now also tells you when the global setting is off instead of silently doing nothing. (#359, reported with excellent diagnostics by @recruiterguy)

Security

• POST /duplicates/invalidate-cache now requires authentication — previously it accepted unauthenticated requests on internet-facing deployments (limited impact: it could only force a duplicate-scan refresh). (#370, found and fixed by @8bitgentleman)

Added

• A :dev docker channel: ghcr.io/new-usemame/calibre-web-nextgen:dev gets every merge as it lands — it's what we run at home. Versioned releases now batch to at most one per day, so release notifications get quieter.

[v4.0.155] – 2026-06-06

Fixed

• Kobo sync: after a Magic Shelf cache rebuild, the per-shelf delivery cursor could silently revert to a stale value, leaving newly-added low-numbered books undelivered until the next shelf change. (#368 follow-up)

[v4.0.154] – 2026-06-06

Fixed

• Kobo sync: adding a book to a Magic Shelf between syncs now reliably delivers it — the sync cursor detects the cache rebuild and re-walks the shelf. (#367 follow-up)

[v4.0.153] – 2026-06-06

Fixed

• Kobo sync: Magic Shelves with more than 100 books no longer re-send the same first 100 books forever — delivery now pages through the whole shelf. (#366 follow-up)

[v4.0.152] – 2026-06-06

Fixed

• Kobo sync: when more than 100 books were pending at once alongside a Magic Shelf refresh, some regular books could be skipped permanently. Nothing is dropped anymore. (#361 follow-up)

[v4.0.151] – 2026-06-06

Fixed

• Kobo sync: Magic Shelf delivery and cache refresh now work in sync-entire-library mode, not just "selected shelves only" mode. (#359)

[v4.0.150] – 2026-06-05

Changed

• Read/unread toggle on the book detail page now shows the action you're about to take (checkmark = "mark as read") instead of the current state, and the read badge uses a consistent checkmark icon everywhere. (#319)

[v4.0.149] – 2026-06-05

Added

• "Reload Metadata" button on the book detail page — re-reads title, author, and other metadata from the book file on disk after you've changed it externally (e.g. in Calibre desktop). (#218, requested by @yodatak)

[v4.0.148] – 2026-06-05

Fixed

• Sorting the Hidden Books page no longer dumps you into the unfiltered library. (#319, reported by @SethMilliken)

[v4.0.147] – 2026-06-05

Fixed

• Kobo sync: libraries with thousands of books imported in one batch (all sharing one timestamp) now sync completely — previously the device could loop on the same batch or skip the remainder. (#347, reported by @andree392)
• Kobo sync: first delivery pass for Magic Shelf membership. (#359)

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Older releases: see the GitHub releases page.