Windows, 2 Monitors, Menu not working

I now have 2 monitors and I run into a menu problem.

I have the Project window on Monitor 1 and the Mixer on Monitor 2.

When in full screen mode the menu is on Monitor 1 (left side). I can click on the bar and the menu opens as you can see on the screenshot. But besides that, the menu bar itself is displayed on Monitor 2 (right screen/Mixer window). When I click on the menu items on the right screen nothing happens. When I click on the blue bar on Monitor 1 (left side) a menu pops up, but there are no menu items on the left side.
Cubase.png

That’s weird. The menu should only be present on monitor one.
Be sure to have the latest graphics drivers installed and check your monitor settings in Windows (right click desktop, Display Settings) Be sure to put the 1st (left) monitor as main display and set the order of the displays as they are. Also set ‘Extend desktop to this display’ in the dropdown menu.

The menu is only on one monitor. Only the menu titles are on the wrong monitor. On the other hand, on the monitor, where the menu is located has not menu titles on the menu bar.