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name: browser-extension-developer 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.

Browser Extension Developer

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

Structure

Copybrowser/
├── 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