browser-extension-template

Cross-browser extension boilerplate - barebones template with Parcel 2, options handler and auto-publishing.

Screenshot of extension options:

Sample extension options output

Features

Getting started

1️⃣ Create your own copy

  1. Click Use this template to make a copy of your own. 😉

Note: When you create a repository from the template, the Template Cleanup workflow will be triggered to delete and edit template-specific resources. Wait a moment until the workflow finishes (you will see a commit pushed with 'Template cleanup' message).

🛠 Build locally

  1. Checkout the copied repository to your local machine eg. with git clone https://github.com/my-username/my-awesome-extension/
  2. Run npm install to install all required dependencies
  3. Run npm run build

The build step will create the distribution folder, this folder will contain the generated extension.

🏃 Run the extension

Using web-ext is recommended for automatic reloading and running in a dedicated browser instance. Alternatively you can load the extension manually (see below).

  1. Run npm run watch to watch for file changes and build continuously
  2. Run npm install --global web-ext (only only for the first time)
  3. In another terminal, run web-ext run -t chromium
  4. Check that the extension is loaded by opening the extension options (in Firefox or in Chrome).

Manually

You can also load the extension manually in Chrome or Firefox.

✏️ Make the first change

  1. For example, edit source\manifest.json to "name": "My Awesome Extension",
  2. Go back to your browser, reload and see the change take effect

Note: Firefox will automatically reload content scripts when the extension is updated, Chrome requires you to reload the page to reload the content scripts.

📕 Read the documentation

Here are some websites you should refer to:

Configuration

The extension doesn't target any specific ECMAScript environment or provide any transpiling by default. The extensions output will be the same ECMAScript you write. This allows us to always target the latest browser version, which is a good practice you should be following.

Parcel 2

Being based on Parcel 2 and its WebExtension transformer, you get all the good parts:

  • Browserlist-based code transpiling (which defaults to just the latest Chrome and Firefox versions)
  • Automatically picks up any new file specified in manifest.json

Auto-syncing options

Options are managed by fregante/webext-options-sync, which auto-saves and auto-restores the options form, applies defaults and runs migrations.

Publishing

It's possible to automatically publish to both the Chrome Web Store and Mozilla Addons at once by adding these secrets on GitHub Actions:

  1. CLIENT_ID, CLIENT_SECRET, and REFRESH_TOKEN from Google APIs.
  2. WEB_EXT_API_KEY, and WEB_EXT_API_SECRET from AMO.

Also include EXTENSION_ID in the secrets (how to find it) and add Mozilla’s gecko.id to manifest.json.

The GitHub Actions workflow will:

  1. Build the extension
  2. Create a version number based on the current UTC date time, like 19.6.16 and sets it in the manifest.json
  3. Deploy it to both stores

Auto-publishing

Thanks to the included GitHub Action Workflows, if you set up those secrets in the repo's Settings, the deployment will automatically happen:

  • on a schedule, by default every week (but only if there are any new commits in the last tag)
  • manually, by clicking "Run workflow" in the Actions tab.

Credits

Extension icon made by Freepik from www.flaticon.com is licensed by CC 3.0 BY.

Extensions created using this template

License

This browser extension template is released under CC0 and mentioned below. There is no license file included in here, but when you clone this template, you should include your own license file for the specific license you choose to use.

CC0