@pfefferle Watch out with editor checkboxes! Super weird behavior (if you use classic meta boxes) in combination with Gutenberg.
For instance, I noticed the AP plugin uses `transition_post_status` and checks `'publish' === $new_status && 'publish' !== $old_status`. With Gutenberg, the first time this hook is run, it will *not* have access to any `$_POST` variables (like a meta box checkbox).
It is then run a 2nd time during which it does, but by then `$old_status` will already be `publish`!