I use 2 monitors, and the problem occurs on both, when I maximize any window, the buttons (minimize, maximize and close) are above or outside the monitor's view, so I can't click on them
I use the bar at the top, on one of the screens, and on that screen, when maximizing any window, the buttons mentioned are under the bar
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It sounds like the monitors require slight adjustment. LCD monitors usually has an auto adjust to make these small adjustments. Or, perhaps the x _ and little square are not configure to appear. With gnome3, if you press ALT+F7 keys, the arrows will move the window. Then, if the control symbols are there, you can see them.
ctrland drag the full screened window with your mouse. – Archisman Panigrahi Nov 07 '21 at 08:24