I had to delete a couple of multi-reference tables and I started getting an error without further description. I noticed the multi-reference tables are not deleted either - Restarted Wappler, and Restarted Mac, didn’t help.
I also noted my system check showing an error as well.
Try hovering over the exclamation mark icon in the database tree to see what is the error there. Or select it and check the property inspector for the error description.
UPDATE: All tables have now disappeared as well. I had about 6-7 tables in there. I tried rolling back to the changes made to DB, however, it did not help either.