[Bug] 4.0.15 hangs on ESR

[DarthGandalf]

Abstract

Since today TST is unusable on FF ESR 115.10.0 on Linux 64bit. It uses 400% CPU, and is either very slow, or just never successfully loads anymore, instead keeping blinking between showing progress bar and not showing. I tried to restart firefox several times, that's how having different results.

I see this in browser console

Key ext-key-id-treestyletab_piro_sakura_ne_jp-sidebar-action of menuitem Tree Style Tab could not be found menu.js:289:19
    accelText chrome://global/content/elements/menu.js:289
    _computeAccelTextFromKeyIfNeeded chrome://global/content/elements/menu.js:296
    render chrome://global/content/elements/menu.js:323
    <anonymous> chrome://global/content/elements/menu.js:170
AbortError: Actor 'Conduits' destroyed before query 'RunListener' was resolved
sendRemoveListener on closed conduit treestyletab@piro.sakura.ne.jp.5772436050333 ConduitsChild.sys.mjs:108
    _send resource://gre/modules/ConduitsChild.sys.mjs:108
    removeListener resource://gre/modules/ExtensionChild.sys.mjs:675
    removeListener resource://gre/modules/ExtensionChild.sys.mjs:940
    register chrome://extensions/content/child/ext-storage.js:175
    removeListener resource://gre/modules/ExtensionCommon.sys.mjs:2869
    revoke resource://gre/modules/ExtensionCommon.sys.mjs:2891
    close resource://gre/modules/ExtensionCommon.sys.mjs:2896
    unload resource://gre/modules/ExtensionCommon.sys.mjs:979
    unload resource://gre/modules/ExtensionPageChild.sys.mjs:282
    unload resource://gre/modules/ExtensionPageChild.sys.mjs:319
    destroyExtensionContext resource://gre/modules/ExtensionPageChild.sys.mjs:479
    observe resource://gre/modules/ExtensionPageChild.sys.mjs:388

I downgraded to 4.0.14 for now, and it works fine.

Steps to reproduce

1. Have >1000 tabs
2. Do nothing
3. Let TST extension automatically update to 4.0.15

Expected result

Actual result

Environment

• Platform (OS): linux
• Version of Firefox: 115
• Version (or revision) of Tree Style Tab: 4.0.15

[piroor]

I've tried TST 4.0.15 + Firefox ESR 115.11.0 on Ubuntu 22.04 (on VirtualBox) but couldn't reproduce such a hanging. Could you collect a performance profile?
https://github.com/piroor/treestyletab/wiki/How-to-inspect-tree-of-tabs#how-to-collect-a-performance-profile

[DarthGandalf]

Not sure what has changed since yesterday, but it managed to load at all today, though slow. It's still 4.0.15

Firefox 2024-05-23 12.13 profile.json.gz

[piroor]

Thanks, I've realized that a change introduced to follow Firefox's change https://bugzilla.mozilla.org/show_bug.cgi?id=1897595 triggers the problem.

[emilio]

The issue is that you're synchronously determining the overflow state on connectedCallback(), the right thing to do is to just let the ResizeObserver callback be invoked once (it will be), or use requestAnimationFrame to batch the initial observations.

[piroor]

@emilio Hmm, the initial "overflow" state is required to know when the state is actually changed, so the synchronous operation

treestyletab/webextensions/common/common.js

Line 994 in 9022cb0

let lastOverflow = (

looks still required... and of course I already throttled detecting "overflow" state on every observations.

treestyletab/webextensions/common/common.js

Line 1002 in 9022cb0

window.requestAnimationFrame(() => {

I can give up to determine the initial state but it looks to mean the initial resizing will be detected as "overflow" or "underflow" here

treestyletab/webextensions/common/common.js

Line 1007 in bf09c98

if (overflow === lastOverflow)

regardless the element's overflow state is actually changed or not.

[piroor]

Anyway this throttling may be effective to reduce needless style computations for tab elements inserted to the DOM tree and immediately removed by quick scrolling.
12359f7
@DarthGandalf Could you try the latest development build? https://github.com/piroor/treestyletab?tab=readme-ov-file#development-builds