As the title says, some (not all) of the popup windows generated by airdroid leave faint lines on my monitor where the window border would have been. These lines stay there until I sign out of Air droid or reboot. I have multiple monitors and the lines only appear on the monitor with Airdroid. Airdroid activates on my main display so I tried changing my main display monitor and the black lines followed the main and airdroid. Not a monitor problem. If no one has a solution, I will have to remove airdroid because the lines are very distracting while working.