This happened in my training project for configuring CT Apps and Services, but I figure it will come in handy in real projects. After I did a search for a category in project explorer Tables, the tables section went from organized by categories to alphabetical. I cannot figure out how to change it back to categories. The only way to get it back to categories was to log out and back in.

One workaround is to briefly switch the search type to 'checked out by me' and then back to 'all' which resets the tables under their parent categories.