Dell XPS 9370 - Kubuntu apps flickering

Hi,

about 2-3 weeks on all Kubuntu applications, when I hover the mouse over menu items, I notice a flicker (see pictures).

If I start a Windows WM within kubuntu, the Windows apps work correctly.

Can anyone help me?

Thanks

Kubuntu 20.04.4 LTS

Kernel version: 5.4.0-107-generic

main@mylaptop:/home# lspci 
00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v6/7th Gen Core Processor Host Bridge/DRAM Registers (rev 08)
00:02.0 VGA compatible controller: Intel Corporation UHD Graphics 620 (rev 07)