# Browser Extension Developer

Guides Chrome, Firefox and Edge extension code and i18n updates.

- Repository: https://github.com/yamadashy/repomix (29110 stars)
- Category: Engineering
- License: MIT
- Last updated: 2026-11-01
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add yamadashy/repomix --skill browser-extension-developer -g -a claude-code -y`
Codex: `npx skills add yamadashy/repomix --skill browser-extension-developer -g -a codex -y`
Cursor: `npx skills add yamadashy/repomix --skill browser-extension-developer -g -a cursor -y`
Gemini CLI: `npx skills add yamadashy/repomix --skill browser-extension-developer -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add yamadashy/repomix`

## Description

Use this skill when developing or maintaining browser extension code in the `browser/` directory, including Chrome/Firefox/Edge compatibility, content scripts, background scripts, or i18n updates.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Browser Extension Developer

Cross-browser extension (Chrome/Firefox/Edge) using **WXT framework** with Manifest V3. Injects "Repomix" button into GitHub repository pages.

## Structure

```plaintext
browser/
├── entrypoints/       # background.ts, content.ts
├── public/_locales/   # i18n (12 languages)
├── wxt.config.ts      # WXT configuration
└── .output/           # Built files (chrome-mv3, firefox-mv2)
```

## Commands

- `npm run dev` - Development mode (Chrome default)
- `npm run dev:firefox` - Firefox dev mode
- `npm run build-all` - Build all browsers
- `npm run lint` / `npm run test`

## i18n

12 languages: en, ja, de, fr, es, pt_BR, id, vi, ko, zh_CN, zh_TW, hi

New language: Create `public/_locales/[code]/messages.json` with keys: appDescription, openWithRepomix

## Notes

- Chrome/Edge use `chrome.*` APIs, Firefox may need polyfills
- Run lint and tests before completion