Got a brand new nasty problem. I have a master doctype and a textpage inheriting a couple of tabs from the master. On the child doctype I have added a few more properties to an inherited tab called "Content".

Today, at some point without obvious reason, all properties that were under inherited tab 'Content' got moved back to 'Generic properties'. If I try to put them back under that 'Content', the cms reports 'saved successful', but no property sticks under the tab in doctype editor.

And when I switch back to content I can see the last updated property under 'Content'. Only one every time, the last one.

Any ideas?