Zed crashes when rendering markdown preview with many gifs

[ralexmatthews]

Reproduction steps

1. Open Zed
2. Open either a large markdown file or a markdown file with invalid image (not sure which is the issue)
3. Press the "preview" button in the top right corner
4. Zed crashes

I encountered it trying to render the index.md file in the all-the-bufo repo.

Zed version and system specs

Zed: v0.230.2+stable.212.53a3365bcf6b1aa17389b21456b6010f294f788f (Zed)
OS: macOS 26.3.1 (a) (Build 25D771280a)
Memory: 36 GiB
Architecture: aarch64

Attach Zed log file

Zed.log

2026-04-08T11:32:39-05:00 INFO  [git::repository] opening git repository at "/Users/me/projects/all-the-bufo/.git" using git binary "/usr/bin/git"
2026-04-08T11:32:39-05:00 INFO  [lsp] Language server with id 3 sent unhandled notification window/logMessage:
{
  "type": 3,
  "message": "[lsp] GitHub Copilot Language Server 1.465.0 initialized"
}
2026-04-08T11:32:39-05:00 INFO  [lsp] Language server with id 3 sent unhandled notification client/registerCapability:
{
  "registrations": [
    {
      "id": "995f7f10-f272-461c-bf10-1a648fce7302",
      "method": "workspace/didChangeConfiguration",
      "registerOptions": {
        "section": [
          "github.copilot",
          "github-enterprise",
          "http",
          "telemetry"
        ]
      }
    }
  ]
}
2026-04-08T11:32:39-05:00 INFO  [lsp] Language server with id 3 sent unhandled notification window/logMessage:
{
  "type": 3,
  "message": "Registering request handler for workspace/didChangeConfiguration failed."
}
2026-04-08T11:32:39-05:00 INFO  [lsp] Language server with id 3 sent unhandled notification window/logMessage:
{
  "type": 3,
  "message": "[certificates] Removed 1 expired certificates"
}
2026-04-08T11:32:39-05:00 INFO  [lsp] Language server with id 3 sent unhandled notification statusNotification:
{
  "busy": false,
  "kind": "Error",
  "status": "Error",
  "message": "You are not signed into GitHub."
}
2026-04-08T11:32:39-05:00 INFO  [lsp] Language server with id 3 sent unhandled notification window/logMessage:
{
  "type": 3,
  "message": "[GithubAvailableEmbeddingTypes] Could not find any available embedding types. Error: noSession"
}
2026-04-08T11:34:31-05:00 ERROR [gpui_macos::metal_renderer] failed to render: scene too large: 0 paths, 1 shadows, 96 quads, 0 underlines, 32373 mono, 8 poly, 0 surfaces. retrying with larger instance buffer size
2026-04-08T11:34:31-05:00 INFO  [gpui_macos::metal_renderer] increased instance buffer size to 4194304
2026-04-08T11:34:32-05:00 INFO  [lsp] starting language server process. binary path: "/Users/me/Library/Application Support/Zed/extensions/work/codebook/codebook-lsp-v0.3.36/codebook-lsp", working directory: "/Users/me/projects/all-the-bufo", args: ["--root=/Users/me/projects/all-the-bufo", "serve"]
2026-04-08T11:34:33-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: unexpected end of file
2026-04-08T11:34:33-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: Format error decoding Gif: unknown block type encountered
2026-04-08T11:34:33-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: Format error decoding Gif: unknown block type encountered
2026-04-08T11:34:33-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: Format error decoding Gif: unknown block type encountered
2026-04-08T11:34:33-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: Format error decoding Gif: unknown block type encountered
2026-04-08T11:34:33-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: Format error decoding Gif: unknown block type encountered
2026-04-08T11:34:33-05:00 ERROR [crashes] thread 'main' panicked at crates/gpui/src/assets.rs:80:40:
index out of bounds: the len is 0 but the index is 0...
2026-04-08T11:34:33-05:00 ERROR [crashes] triggering a crash to generate a minidump...
2026-04-08T11:35:55-05:00 INFO  [zed] ========== starting zed version 0.230.2+stable.212.53a3365bcf6b1aa17389b21456b6010f294f788f, sha 53a3365 ==========
2026-04-08T11:35:55-05:00 INFO  [crashes] crash signal handlers installed
2026-04-08T11:35:55-05:00 INFO  [crashes] spawning crash handler process
2026-04-08T11:35:55-05:00 INFO  [zed] Using git binary path: "/Applications/Zed.app/Contents/MacOS/git"
2026-04-08T11:35:55-05:00 INFO  [crashes] connected to crash handler process after 100ms
2026-04-08T11:35:55-05:00 INFO  [crashes] crash handler registered
2026-04-08T11:35:55-05:00 INFO  [extension_host] extensions updated. loading 20, reloading 0, unloading 0
2026-04-08T11:35:55-05:00 INFO  [auto_update] Auto Update: checking for updates
2026-04-08T11:35:55-05:00 INFO  [workspace] Rendered first frame
2026-04-08T11:35:55-05:00 INFO  [client] set status on client 0: Authenticating
2026-04-08T11:35:55-05:00 ERROR [crates/agent_ui/src/agent_panel.rs:129] Error("unknown variant `ClaudeCode`, expected one of `NativeAgent`, `TextThread`, `Custom`", line: 1, column: 44)
2026-04-08T11:35:55-05:00 ERROR [gpui_macos::metal_renderer] failed to render: scene too large: 0 paths, 1 shadows, 104 quads, 0 underlines, 32390 mono, 7 poly, 0 surfaces. retrying with larger instance buffer size
2026-04-08T11:35:55-05:00 INFO  [gpui_macos::metal_renderer] increased instance buffer size to 4194304
2026-04-08T11:35:55-05:00 INFO  [client] set status on client 247634: Authenticated
2026-04-08T11:35:56-05:00 INFO  [node_runtime] Node runtime install_if_needed
2026-04-08T11:35:56-05:00 INFO  [git::repository] opening git repository at "/Users/me/projects/all-the-bufo/.git" using git binary "/usr/bin/git"
2026-04-08T11:35:56-05:00 WARN  [node_runtime] using Zed managed Node.js at /Users/me/Library/Application Support/Zed/node/node-v24.11.0-darwin-arm64 since checking system Node.js failed with error: node at /Users/me/.nvm/versions/node/v20.10.0/bin/node is too old. want: 22.0.0, got: 20.10.0
2026-04-08T11:35:57-05:00 INFO  [copilot] Checking Node.js version for Copilot at: "/Users/me/Library/Application Support/Zed/node/node-v24.11.0-darwin-arm64/bin/node"
2026-04-08T11:35:57-05:00 INFO  [copilot] Node.js version 24.11.0 meets Copilot requirements (>= 20.8.0)
2026-04-08T11:35:57-05:00 INFO  [lsp] starting language server process. binary path: "/Users/me/Library/Application Support/Zed/node/node-v24.11.0-darwin-arm64/bin/node", working directory: "/", args: ["--experimental-sqlite", "/Users/me/Library/Application Support/Zed/copilot/node_modules/@github/copilot-language-server/dist/language-server.js", "--stdio"]
2026-04-08T11:35:57-05:00 INFO  [copilot] Checking Node.js version for Copilot at: "/Users/me/Library/Application Support/Zed/node/node-v24.11.0-darwin-arm64/bin/node"
2026-04-08T11:35:57-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: unexpected end of file
2026-04-08T11:35:57-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: Format error decoding Gif: unknown block type encountered
2026-04-08T11:35:57-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: Format error decoding Gif: unknown block type encountered
2026-04-08T11:35:57-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: Format error decoding Gif: unknown block type encountered
2026-04-08T11:35:57-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: Format error decoding Gif: unknown block type encountered
2026-04-08T11:35:57-05:00 ERROR [gpui::asset_cache] Failed to load asset: image error: Format error decoding Gif: unknown block type encountered
2026-04-08T11:35:57-05:00 ERROR [crashes] thread 'main' panicked at crates/gpui/src/assets.rs:80:40:
index out of bounds: the len is 0 but the index is 0...
2026-04-08T11:35:57-05:00 ERROR [crashes] triggering a crash to generate a minidump...
2026-04-08T11:36:32-05:00 INFO  [zed] ========== starting zed version 0.230.2+stable.212.53a3365bcf6b1aa17389b21456b6010f294f788f, sha 53a3365 ==========
2026-04-08T11:36:32-05:00 INFO  [crashes] crash signal handlers installed
2026-04-08T11:36:32-05:00 INFO  [crashes] spawning crash handler process
2026-04-08T11:36:32-05:00 INFO  [zed] Using git binary path: "/Applications/Zed.app/Contents/MacOS/git"
2026-04-08T11:36:32-05:00 INFO  [crashes] connected to crash handler process after 100ms
2026-04-08T11:36:32-05:00 INFO  [crashes] crash handler registered
2026-04-08T11:36:36-05:00 INFO  [extension_host] extensions updated. loading 20, reloading 0, unloading 0
2026-04-08T11:36:36-05:00 INFO  [auto_update] Auto Update: checking for updates
2026-04-08T11:36:36-05:00 INFO  [workspace] Rendered first frame
2026-04-08T11:36:36-05:00 INFO  [client] set status on client 0: Authenticating
2026-04-08T11:36:36-05:00 INFO  [node_runtime] Node runtime install_if_needed
2026-04-08T11:36:36-05:00 ERROR [crates/agent_ui/src/agent_panel.rs:129] Error("unknown variant `ClaudeCode`, expected one of `NativeAgent`, `TextThread`, `Custom`", line: 1, column: 44)
2026-04-08T11:36:36-05:00 ERROR [gpui_macos::metal_renderer] failed to render: scene too large: 0 paths, 1 shadows, 104 quads, 0 underlines, 32390 mono, 7 poly, 0 surfaces. retrying with larger instance buffer size
2026-04-08T11:36:36-05:00 INFO  [gpui_macos::metal_renderer] increased instance buffer size to 4194304
2026-04-08T11:36:36-05:00 INFO  [client] set status on client 247634: Authenticated
2026-04-08T11:36:37-05:00 WARN  [node_runtime] using Zed managed Node.js at /Users/me/Library/Application Support/Zed/node/node-v24.11.0-darwin-arm64 since checking system Node.js failed with error: node at /Users/me/.nvm/versions/node/v20.10.0/bin/node is too old. want: 22.0.0, got: 20.10.0
2026-04-08T11:36:37-05:00 INFO  [git::repository] opening git repository at "/Users/me/projects/all-the-bufo/.git" using git binary "/usr/bin/git"
2026-04-08T11:36:38-05:00 INFO  [copilot] Checking Node.js version for Copilot at: "/Users/me/Library/Application Support/Zed/node/node-v24.11.0-darwin-arm64/bin/node"
2026-04-08T11:36:38-05:00 INFO  [copilot] Checking Node.js version for Copilot at: "/Users/me/Library/Application Support/Zed/node/node-v24.11.0-darwin-arm64/bin/node"
2026-04-08T11:36:38-05:00 INFO  [copilot] Node.js version 24.11.0 meets Copilot requirements (>= 20.8.0)
2026-04-08T11:36:38-05:00 INFO  [lsp] starting language server process. binary path: "/Users/me/Library/Application Support/Zed/node/node-v24.11.0-darwin-arm64/bin/node", working directory: "/", args: ["--experimental-sqlite", "/Users/me/Library/Application Support/Zed/copilot/node_modules/@github/copilot-language-server/dist/language-server.js", "--stdio"]
2026-04-08T11:36:38-05:00 INFO  [copilot] Node.js version 24.11.0 meets Copilot requirements (>= 20.8.0)
2026-04-08T11:36:38-05:00 INFO  [lsp] starting language server process. binary path: "/Users/me/Library/Application Support/Zed/node/node-v24.11.0-darwin-arm64/bin/node", working directory: "/", args: ["--experimental-sqlite", "/Users/me/Library/Application Support/Zed/copilot/node_modules/@github/copilot-language-server/dist/language-server.js", "--stdio"]
2026-04-08T11:36:38-05:00 INFO  [lsp] starting language server process. binary path: "/Users/me/Library/Application Support/Zed/extensions/work/codebook/codebook-lsp-v0.3.36/codebook-lsp", working directory: "/Users/me/projects/all-the-bufo", args: ["--root=/Users/me/projects/all-the-bufo", "serve"]

[miguelraz]

Thanks for the report!

I repro'd the crash by following your exact steps with the all-the-bufo repo.

I'm linking the Sentry ID to this.

[sentry]

Sentry Issue: ZED-6CP

[ralexmatthews]

Sweet, thank you for looking into this 🙂