Metaboxes unable to be moved to side panel anymore?

[rklis]

Hi community,
I am not entirely sure if this falls under WP or Gutenberg but at some point during recent updates moving metaboxes between main Gutenberg main screen and side panel stopped working.

Before, you were able to click on this button to move metaboxes between main content and side panels. Now in some cases it still works, however, it seems like when you move all metaboxes to the content, that's where it's stuck (like on the image) and you can't move them around anymore. Both first and last metabox have their arrows going out disabled.