Restarting Firefox/Session restore resizes random windows (most of them) to half the length of the screen. How do I fix this? (Deleting localstore does not help)

Restarting Firefox/Session restore resizes random windows (most of them) to half the length of the screen. I've had to resize ALL of my windows to maximized on every single session restore for -years- now and I would like to know why this hasn't been fixed yet. How do I fix this? Deleting localstore does nothing to eleviate this problem.