While Full-Site Editing is still experimental, themes need a way to require Gutenberg be installed as a plugin, with the Full Site Editing experiment enabled.
The PHP file here will do the following:
- Show an admin notice stating this is an experimental theme
- Check if Gutenberg is installed as a plugin
- If Gutenberg is not installed, allow users to install it with the click of a button.
- Check if Gutenberg is Activated
- Check if Gutenberg has the "Full Site Editing" experiment enabled.
- If Gutenberg is not activated or the experiment is not enabled, allow users to activate them with the click of a button.
- If the user switches to a non-FSE theme, deactivates the experiment.
Everything runs on AJAX so there are no page refreshes.
Simply grab the contents of the require-gutenberg.php file and paste them in your functions.php file. Alternatively you can include it as a separate file.
Once you copy the code to your theme, replace textdomain inside the file with your theme's text-domain.
This script is released by Ari Stathopoulos and the WordPress Themes Team under the MIT license.