Disable Gutenberg and keep the classic editor
First of all, what is Gutenberg editor?
Since the release of WordPress 5.0, Gutenberg is the default editor in WordPress.
Why disable Gutenberg editor?
Many WordPress users are working with the classic editor for years, and are more comfortable with it.
How to disable it, Marko?!
Add the following code to your
add_filter('use_block_editor_for_post', '__return_false', 10);