Feature Request: Custom Markdown Preview Theming / Styling

[iamdhakrey]

Requesting the ability to customize the styling (CSS) of the Markdown Preview pane independently of the main editor theme.

The current reliance on the editor's theme prevents users from:

Ensuring Consistency: The preview often doesn't match the final published look of documentation (e.g., GitHub Pages, wikis), which breaks visual parity.

Improving Readability: Users cannot adjust typography (e.g., line height, spacing, or header sizes) specifically for the reading experience without changing their entire coding theme.

Proposed Solution / Implementation Ideas
We propose adding a mechanism for custom styling the Markdown Preview content:

Option 1: Dedicated CSS File Support (Preferred)

Allow users to inject one or more custom CSS files via settings.json (relative to home or workspace).

{
  "languages": {
    "Markdown": {
      "preview_styles": [
        "~/.config/zed/markdown_preview.css"
      ]
    }
  }
}

Option 2: Theme-Specific Overrides

Allow theme authors to define specific style properties for rendered Markdown elements (headings, links, lists) within the theme schema itself.

This flexibility will greatly enhance Zed's utility for documentation and technical writing.

[xpe]

Friendly amendment:

Option 3: 1 or 2 or 1→2

• Support both Option 1 and Option 2, above.
• 1→2: In addition, allow the settings.json block (Option 1) to reference themes, whether built-in or installed via extensions (Option 2).

(Does this make sense? I haven't looked specifically what the syntax could look like yet.)

[alexojegu]

For now, it would be enough for me if, instead of using text, it used editor.foreground. If the background is editor.background, it makes sense for the foreground to be editor.foreground.

As it stands, I can't really use it—it bothers my eyes.

By the way, the same thing happens with commits (background = editor.background and foreground = text) .

[michael-ford]

Bumping this thread with a narrower proposal, since the original suggestions (custom CSS, full theme-schema markdown styling) are both fairly large surface-area changes that may be why no PR has materialized.

The pain: in current Zed, h1/h2/h3 in the markdown preview render at nearly identical sizes, so document hierarchy is essentially invisible. This is increasingly relevant as more people use Zed as a lightweight markdown viewer alongside agentic coding tools (Claude Code, Cursor, etc.) where reading AI-generated plans, specs, and reports is a daily activity. For that use case Zed is an excellent minimal alternative to VS Code — except the markdown rendering undersells it.

Minimal proposal: add a markdown_preview settings block with per-level heading sizing, e.g.:

"markdown_preview": {
  "heading_scale": [2.0, 1.6, 1.3, 1.15, 1.05, 1.0]
}

Multipliers on buffer_font_size, defaults preserve current behavior. No theme schema changes, no CSS engine, no new rendering pipeline — just lifts existing hardcoded sizes into settings.

Questions before I open a PR:

1. Would you accept this as a stepping-stone, or do you want to wait for a fuller theming solution?
2. Preference on the shape — array of multipliers, named fields (h1, h2, ...), or absolute sizes?
3. Should weight/color be in scope of the same PR or a follow-up?

Happy to sign the CLA, write tests, and include before/after screenshots. Would rather check before sinking a weekend into it.

[thorizer]

there is some great ideas here. Current markdown preview is hard to look at, even editor is better than the preview. Markdown is more important than code nowadays, without it, the ide by itself is not enough @defunkt

[samvaran]

I think just a slightly better default styling would be a great place to start. To echo @thorizer the current markdown preview is hard to parse visually. There are several sources of inspiration that do a better job at the moment, and seem to be broadly appealing: Cursor's markdown preview, Bear (the Mac App), Notion, Graphite, even GitHub itself.

Honestly if Zed had more or less visual parity with GitHub's README markdown I think I'd be a happy camper, and my need for a fully custom theme would be greatly reduced.

[andyinabox]

I agree with @samvaran, just a better default viewer similar to GitHub's would make me happy.

[diogosaitotakeuchi]

Coming here to echo the sentiment, the current markdown preview is terrible to the point reading the markdown in the editor is better (not ideal though). Sounds like an easy fix for a fast growing demand and necessity.

[xpe]

Yep, it is impressive (in a bad way) to see Markdown look so awful. Not "retro", not "classic". Just fugly.

[okmtx]

I've been spending way less time vibe-coding with source code open side by side.
Instead, I'm spending more and more time reading through markdown and mermaid files, then dictating comments via voice input.

There's a rapidly growing need for a beefed-up Markdown Preview that lets you comment and interact at the spec layer — basically turning it into a lightweight editor for design docs.
That's exactly why I'm hoping Zed, with its fast startup, will step up its Markdown Preview game.

[LexRiver]

Just the ability to change the colors in zed's theme for MD preview would be great.

[PrimeTimeTran]

One of the things I'd really like to see if support for Wikilinks so that Zed can be a replacement for Obsidian.
I have a "knowledge base" monorepo where I basically keep all my notes on programming, life, blog, etc. Inside of it I have my actual projects. If Zed supported the following it'd be awesome.

• [[Link to file in project]]
• [[#Link to section in file]]
• [[File in Repo/Project/Monorepo|Alias for that file shown in preview mode]]
• [[File in Repo/Project/Monorepo|Alias for that file shown in preview mode#anchor in other file]]

I'll open a PR when someone from Zed confirms ya'll are interested in this functionality.

[sonalkarmakar]

I write notes in Obsidian and store them in GitHub and GitLab. I'm somewhat interested in this, but I found that Obsidian supports Markdown syntax of GitHub and GitLab, so I just use them in Obsidian to keep my notes connected when accessing from those platforms.

Obsidian syntax is required only when you use the unique features it offers. If you don't need those features, you can work with regular Markdown syntax in Obsidian without issues.

[punitsu]

I have been spending more and more time reading and reviewing md, and the current preview is awful. I often end up switching to another app just to preview the markdown properly, because reviewing it here is difficult.

+1 to custom styling, even for the default opinionated preview, better spacing would make a huge difference

[Bosbolo]

same here line-height is to tight

[sonalkarmakar]

I think both the Markdown renderer and editor need a rework rather than just theming. I have found the following issues bothering me with Markdown:

• HTML tags like <ins> are not rendered. It's the recommended method of underlining in GitHub.
• The editor is inconsistent with auto-completing HTML tags. I noticed that if the suggestion pops up, the auto-completion stops for the next few lines.
• Italics with underscore (_like this_) is rendered but not auto-completed or wrapped by the editor.
• Monospace/code fonts appear larger than normal fonts in a Markdown render. I believe this is due to my font settings in Zed, but I don't think different font types should have different sizes in the same document.
• Bold inside link text ([**bold text**](https://example.com/)) doesn't have the link's underline or colour, it's rendered as bold only.
• No section/page linking suggestions by default. You have to install and configure extensions for that. VS Code has this built-in.
  • Side note: I tried Markdown Oxide for this, but it's generating links like [text](<Filename#My Heading>) instead of [text](#my-heading). If anyone knows how to change it, please let me know.

[ahmet-cetinkaya]

Yes, markdown preview should be themeable/customizable.

[xpe]

INT. U.S.S. ENTERPRISE-D — BRIDGE

PICARD sits in the command chair, tea in hand. The tea has gone cold. He knows it, and he drinks it anyway, as penance.

PICARD
Computer. Access the Zed Industries repository. Discussion four-three, three-eight-four. Full record — and spare me the notification digest.

COMPUTER (V.O.)
Working. Discussion opened in November. Subject: custom theming for the markdown preview. Five participants. Three proposals. Current status: open.

PICARD
"Open." (a bitter sip) A generous word, Computer, for a door no one intends to walk through.

He rises. Tugs his uniform.

PICARD (CONT'D)
Walk me through it. The original request: a full theming system. Then a second proposal — syntax colors only. Then a third: a single CSS variable. Each participant asking for less than the one before. This was not deliberation, Number One. This was a bidding war conducted in reverse, against an opponent who never arrived at the table.

RIKER
(leaning on one armrest, the full Riker lean)
Maybe they're softening up the maintainers, sir.

PICARD
The maintainers, Number One, have not spoken since stardate — (checks) — November.

He turns to the science station.

PICARD (CONT'D)
Mr. Data. Explain to me the command structure of this... assembly. Who presides?

DATA
No one, Captain. A GitHub discussion is a curious institution. The participants possess no authority to implement what they propose. Commenting confers no standing. The maintainers alone may act, but are under no obligation to read, respond, or acknowledge that the discussion exists.

PICARD
Then in what sense is it a discussion?

DATA
An interesting question, sir. Structurally it most resembles a message placed in a bottle — except the bottle is indexed, searchable, permanently archived, and periodically bumped to the surface by a participant asking, quote, "any updates on this?"

WORF
(from tactical, with genuine disgust)
If they have no power, why do they speak?

DATA
Hope, Lieutenant. Also, thumbs-up reactions.

WORF
And these... reactions. They compel action?

DATA
They compel nothing. They are votes in an election with no office, tallied by a government that does not check the returns.

A silence. WORF looks personally offended by the entire concept.

PICARD
(crossing slowly to the viewport)
So we have five individuals, petitioning no one, in a forum without a chair, accumulating endorsements that convert to nothing, progressively reducing their demands to appease an authority that has given no indication it is listening — or exists.

DATA
That is an accurate summary, sir.

PICARD
I have negotiated with the Sheliak, Mr. Data. They at least answered hails.

TROI
(quietly, from his left)
Captain — for what it's worth, I sense no anger from the participants. Only patience. Enormous, unsettling patience.

PICARD
That is precisely what concerns me, Counselor. Anger disperses. Patience accumulates. Somewhere in that thread a user is composing their fourth comment in eight months, and they believe — they still believe — that specificity is the problem. That if they can only phrase the request narrowly enough, precisely enough, smally enough, someone will finally—

(he stops himself; composes)

The Romans had a senate that debated endlessly while executive power sat elsewhere, indifferent. At least the senators were paid.

RIKER
Permission to speak freely, sir.

PICARD
Granted.

RIKER
It's a feature request for preview colors, Captain.

PICARD
(turning, with terrible calm)
It is a system, Will. A system in which participation is free, authority is invisible, persuasion is measured in emoji, and the record of one's unanswered petition is preserved — forever — as a monument to the asking. I have stood in the ruins of civilizations that documented their decline more briskly. If we are trapped in some computational-social structure that generates deliberation without decision, I should like to know whether that is a flaw in the design... or the design.

Beat. He straightens.

PICARD (CONT'D)
So. Final question, and I want it plainly. Has any maintainer engaged — assigned it, triaged it, applied so much as a label — or are those five souls still adrift?

COMPUTER (V.O.)
No maintainer activity detected. One new thumbs-up reaction since your query began.

PICARD closes his eyes. Holds. Opens them.

PICARD
...Make it stop.

SMASH CUT TO BLACK.

(Author: Fable, prompted and prodded by myself)

[ZenBenR]

I really appreciated this 🖖

[legleux]

This was great!

[punitsu]

haha