My TB got updated to this version but messed up functionality. Highlighted message headings such as Inbox, Sent etc remain highlighted until you mouse over, then they get removed. This also happens with messages, until the mouse moves over them they are hidden, also the tabs become invisible until, again, the mouse is moved over them. Switching to safe mode brings back proper functionality, even removing add ons does not cure it (I only have a dictionary installed). Running W10 home v1909 Any help would be appreciated. Colin.