Content scripts

Injects a small badge into every web page you visit.

Runs on Chrome, Edge, Firefox · Manifest V3 · Surfaces: content script, background service worker · Styling: CSS

Create this project

npx extension@latest create my-content --template content
cd my-content
npm install
npm run dev

Permissions it asks for

  • activeTab
  • scripting
  • <all_urls>

Source on GitHubDocumentation

extension.devDocumentation for extension.dev