wxt
DevelopmentWXT browser extension patterns for entrypoints, background service workers, content scripts, side panels, storage, permissions, host permissions, browser compatibility, and build commands. Use when editing apps/tab-manager, wxt.config.ts, src/entrypoints, extension manifests, or @wxt-dev/storage usage.
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WXT Browser Extensions
Reference Repositories
- WXT - Browser extension framework used by
apps/tab-manager
Upstream Grounding
When WXT entrypoint discovery, manifest generation, browser targets, storage, content scripts, background service worker lifecycle, or build output affects correctness, ask DeepWiki a narrow question against wxt-dev/wxt. Verify decisive details against local wxt.config.ts and generated output.
Epicenter Shape
apps/tab-manager is side-panel first: no popup and no content scripts today. The background service worker is minimal and opens the side panel from the extension action.
Entrypoints
- Entrypoints live under
src/entrypoints, zero or one level deep. - Use
defineBackgroundfor background service workers anddefineContentScriptfor content scripts. - Put browser API runtime work inside the entrypoint
mainfunction because WXT imports entrypoint modules during build in Node. - Do not make background
mainasync. Kick off async setup inside it. - Use browser flags and feature detection for cross-browser APIs, not types alone.
Manifest, Storage, And Commands
- Declare
permissionsandhost_permissionsexplicitly inwxt.config.ts. - Use
@wxt-dev/storagewith area-prefixed keys and include thestoragepermission. - Keep host permissions as narrow as the feature allows. Use
<all_urls>only when the extension genuinely needs all tab URLs or favicons. - Local scripts are WXT commands:
wxt prepare,wxt build,wxt zip, and browser flags such as-b firefox. - From the repo root, prefer the existing Bun scripts for the Tab Manager app instead of calling package-manager alternatives.