I've had a few problems where I create or edit a page and all edit controls are grayed out and I can't make any changes.
This is currently happening when I go to create a page from the Meeting Notes template. The page is created fine, I just can't make any change.
If I close, then the page remains as an unpublished page. If I try to publish, I get "There was an error processing the request.".
A colleague of mine can perform this action without issue in the same space.