See the attached image! 
This is on Windows 10. Direct screenshot. Also title text is gone (where it says Cubase 10 - Project name etc.)
2560x1440 monitor. HiDPI not used, ever.
Hi,
What graphics card do you use? Could you try to install the latest driver, please?
Nvidia GTX 750. Driver is actually the latest version, 417.01. I updated a few days ago.
Never had a gfx glitch with Cubase as far as I remember. The glitch happened with a VSTi called Hexeract, but I have been using it on 9.5 without any gfx issues.