I find that my desktop is about a centimeter larger than my monitor. The menu bar is sometimes hidden on top, and I have to move my mouse to the top for to reveal. Dock sometimes disappears from the bottom. (It not set to auto-hide, it's just hidden because the desktop is too big.)
This occurs on my external monitors and on my built-in monitor (even when there is no built-in monitor).
Changing the resolution does not help.