From extension stores

Scratch Addons is available in these stores.

StoreInstallSupported browsersSystem requirements
Chrome Web StoreInstall for Chrome Web StoreGoogle Chrome 96+
Microsoft Edge 96+
Opera 82+
Brave 1.33+
Vivaldi 5.0+
Chromium 96+
Windows 7+
OS X / MacOS 10.11+
Add-ons for FirefoxInstall for Add-ons for FirefoxMozilla Firefox 109+Windows 7+
OS X / MacOS 10.12+
Microsoft Edge Add-onsInstall for Microsoft Edge AddonsMicrosoft Edge 96+Windows 7+
OS X / MacOS 10.11+

From source

Unlike the store releases, installing from source requires a browser based on Chromium 121+ or Firefox 121+.

About GitHub releases

The releases page contains the code and installation files for all development builds of Scratch Addons, as well as the mirror of the store builds.

Cloning the repository

This is the recommended way to install Scratch Addons for development purposes, assuming you have Git installed.

If you plan on contributing, fork the repository on GitHub first and then clone the fork, replacing <username> with your Github username.

$ git clone<username>/ScratchAddons.git

To update Scratch Addons, first cd into its folder, and then run the following commands.

$ git fetch
$ git pull

Remember to also update Scratch Addons from the browser.

Downloading the Zip

This method is not recommended for development unless Git cannot be installed on the system since it will need to be manually repeated every time you update Scratch Addons.

If you don not have Git installed, use this method instead.

  1. Go to the repository and find the download code button.

  2. Click it and select “Download ZIP”.

  3. Extract the archive into a folder.

Installing on Google Chrome or Microsoft Edge

To load the extension into Google Chrome and most Chromium-based browsers such as Microsoft Edge, Opera, Brave or Vivaldi:

  1. Go to chrome://extensions

  2. Turn on “Developer mode” in the top-right corner

  3. Click “Load unpacked” and select the ScratchAddons folder.

To update the extension when testing, click the refresh icon on the extension’s card.

The “Unrecognized manifest key” warnings may safely be ignored, since they are required by Firefox.

Installing on Mozilla Firefox

To load the extension into Mozilla Firefox:

Addons loaded into Firefox this way are temporary and must be reloaded every time the browser is restarted. Because of this Chrome is recommended for development, but everything is still expected to work on Firefox.
  1. Go to about:debugging

  2. Click “This Firefox” on the sidebar

  3. Click “Load Temporary Add-on…”

  4. Select the manifest.json file in the ScratchAddons folder.

  5. If a permission tab opens, click the “Enable” button.

To reload the extension when testing, click the “Reload” button on the extension’s card.

The unexpected WebExtension manifest property warnings may safely be ignored, since they are required by Chrome.