WP5.3 — Invalid arg. supp. for foreach class-wp-post-type.php

Hello Guys!
Another problem that raised on WP5.3 since my update yesterday.

Invalid argument supplied for foreach in (...)\wp-includes\class-wp-post-type.php

MB Custom Post Type is throwing me this permanent warning on WP Admin after I create a custom post type WITH JUST THE TITLE FIELD, nothing else. Yes, it's intentional... I use only the title and add a buch of metaboxes to handle the content. Don't need the traditional editor (or the nightmarish Gutenberg) for my CPT.

If I add EDITOR field, the warning is gone.
Can you guys take a look?
Back on WP 4.2.X this was not happening.

Thank you!
G.