[B4 Pages] Can't delete folder in Pages

  Perhaps related to previous bug reported with the table cms_url_store.

I tried to delete an empty folder in Pages. But I can't delete this folder because of the following error.

3T260/1     Database pages cannot be deleted. 

First it is a folder and not a page. The folder is empty. There has never been a page with the same name with a database in it.