After updating TB from 112 to 115 the display window is after starting mostly blank. The email folder tree is hidden left. When I pull it to standard location, when I click to the message folder to see the emails, they do not appear on the right. I need then to reset the screen setting to get to the standard classic theme. This holds only short time and again I have a blank screen as attached. When I click to File and then on Exit, it takes very long to close the TB. Closing the TB wit the right cross top works immediatelly. In my case I have a big folders (few GB each) and multiple emal accounts. I really have to say, that in speed and friendly usage is the 115 step backwards from 112.