All pull-down menus show under UE4 window

Hi

It’s hard to screen this problem, actually all context menu do not showing. I click on right mouse button and got nothing. In fact, a menu “appears” and if I blindly move the cursor and press the left button will be selected some of the menu items. In material and blueprint editor I got this. Same things with Epic Games Launcher.

Some menu appearing when I reducing size the editor window.

My dxdiag

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