Gist for my tutorial "Building a Gutenberg sidebar plugin Part 1: Registering the plugin with (oop) php". https://vanaf1979.nl/making-a-gutenberg-sidebar-plugin-part-1-registering-the-plugin-with-oop-php/

meatatags-class-adding-actions.php

<?php
class MetaTags {

    ...

    public function register() : void {

        \add_action(
            'enqueue_block_editor_assets',
            array( $this , 'enqueue_styles' ),
            999
        );

        \add_action(
            'enqueue_block_editor_assets',
            array( $this , 'enqueue_scripts'),
            999
        );

        \add_action(
            'init',
            array( $this , 'register_meta_fields' ),
            1
        );

    }

}
?>