Clicking on the Shared button used to bring up a dialog box - it no longer does, it does nothing. I then went to the 3 dots menu and clicked on the "share" option. Again, nothing happens - do dialog box, no nothing. So currently, if I shared a document, I can now no longer unshare it. This happens with any and all items I have shared in the past.

I also just tried to share an object that I had never shared before and clicking on the 'share' options button does nothing.