I finally noticed a problem. I downloaded mail tab for gmail free version. It used to works fine. Except after installing mojave when I click on the mail icon on the top of the menu bar I can not read the messages. The window opens extra wide and cuts off the left side so I only see part of the message. If I keep it in the dock and quit the program and then reopen it it shows the opposite. The right side gets cut off and the left side is fine except just half an inch gap on the left. But I can see most of the message. But as soon as I click on the mail icon on the menu bar or the desktop and then go back to the mail tab its back to cutoff on the left side and I have quit again.