When I open a single settings window from outside the system settings the windows is larger than the screen with no side scroll bars the only way to reache the apply, defaults, ... etc. buttons is using Alt + click to move the window until I can reach the bottom to recreate: Press Alt +F2 > Type: display screenshot: https://pasteboard.co/GE4CrBi.png (Maui)
*** This bug has been marked as a duplicate of bug 354227 ***