Context menu is opened into a wrong screen

Issue is demonstrated using Qt Assistant but, this is not an Qt Assistant specific issue.

Context menu is shown in a wrong screen. Screenshots attached from the issue.

Prequisites:

• connect another display to test machine
• setup screen sharing from Preferences -> display
• align both screens to bottom
• set right screen resolution to scaled (1360x768)
• leave left screen resolution to default

Steps to reproduce:

• open Qt Assistant
• move it to the right screen
• open context menus

It might take a few try, but it's reproducible quite easily.