Initial

A minimal extension that loads in your browser, ready to build on.

Runs on Chrome, Edge, Firefox · Manifest V3 · Styling: CSS

Create this project

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

!Powered by Extension.js

Starter Extension (init)

A minimal extension that loads in your browser, ready to build on.

What you'll see: A minimal extension wired with dev / build / preview scripts.

How it works: A JavaScript extension scaffold ready for extension dev / extension build.

The default starter: what npx extension@latest create <name> produces when no --template is passed. A small sidebar panel wired with dev / build / preview scripts.

Try it locally

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

A fresh browser window opens with the extension already loaded.

Project layout

src/
├── images/
│   ├── icon.png
│   └── javascript.png
├── index.js
└── manifest.json

Commands

Cloned this repo instead? The examples ship without npm scripts, so run Extension.js directly from the example directory. Run npm install first when the example declares dependencies.

dev

Run the extension in development mode. Target a browser with --browser:

npx extension@latest dev .                  # Chromium (default)
npx extension@latest dev . --browser=chrome
npx extension@latest dev . --browser=edge
npx extension@latest dev . --browser=firefox

build

Build for production:

npx extension@latest build .                # Chromium (default)
npx extension@latest build . --browser=firefox
npx extension@latest build . --browser=edge

preview

Preview the production build with the bundled browser:

npx extension@latest preview .

Tests

This template ships an end-to-end check (template.spec.ts) validated by the examples-repo CI on every commit.

Learn more

extension.devDocumentation for extension.dev