Automatic anchor IDs?

What makes them work?

It would appear that the automatic anchor IDs feature that was added in WordPress 5.9, and/or a certain version of Gutenberg, has been disabled from Gutenberg 12.7.0 onwards.

If you want to enable automatic anchor IDs in your theme you will need to use some code in functions.php.

add_filter(
        'block_editor_settings_all',
        static function( $settings ) {
                $settings['__experimentalGenerateAnchors'] = true;
                return $settings;
        }
);

This site is currently running:

WordPress version:5.9.3
Gutenberg version:12.9.0