Right-click menu goes off screen if you open it too close to the window's borders

[CubixL]

Describe the bug
If the menu is opened too far to the right, some of it gets cut off.

To Reproduce
Steps to reproduce the behavior:

1. Right-click near the right side of the window
2. Menu gets cut in half

Expected behavior
The menu to clip back in the window

Screenshots
If applicable, add screenshots to help explain your problem.

Additional context
The menu doesn't get cut off at the bottom because of the sliding animation that "pushes" the menu back up.

[Bentroen]

Commit 5ab8d59 pushes offending menus to the left, but they close as soon as you try to reach them with the mouse. I'm reopening this so we can investigate a proper fix.

NBS.198.mp4