issue after enlarging firefox window

Hello after the last update (72.0.1), when enlarging the firefox window the fill all the screen, there a little issue in the upper frame since my taskbar is in the upper side of my screen and it's tranparant, the upper frame surpasse the taskbar and since this last one is transparant I can realy see it and it's disturbing. I must not keep the window enlarged in order to not have the display issue but the windows keep moving sometimes cause it's not locked. I didn't have the issue with the previous version.