Problem with my display on Ubuntu 18.04, 20.04 and Lubuntu 18.04.5 - sreen is flashing while booting my system or turn on/turn off my display

Dear Launchpad Community,

I have problem with my display on all version of Ubuntu system. It doesn't matter what version I will install. I checked this on Ubuntu 18.04.5, Ubuntu 20.04, Ubuntu 20.04.1, Lubuntu 18.04.5. My screen is flashing for one second when I boot my system or if I will turn on/turn off my display. My screen is flashing (white image) for one second. What is a problem? I think that this can be driver problem. I have this same problem on other computer. On these computers I have Radeon graphic card.

Some outputs from terminal:

lshw -C video

*-display
       description: VGA compatible controller
       product: RS880M [Mobility Radeon HD 4225/4250]
       vendor: Advanced Micro Devices, Inc. [AMD/ATI]
configuration: driver=radeon latency=0

uname -ar
5.4.0-66-generic #74~18.04.2-Ubuntu x86_64 GNU/Linux

I hope that you can help. I think that this is driver problem or maybe it is a normal on Linux systems. I don't have this issue on Windows family system.

I founded on askubuntu some solution. I can add to the GRUB nomodeset option and this help me for the one of the machines. Flickers is gone but system works slower and with lower resolution. On my machine with RS880M this option is not possible because this cause problems with my hardware and I can see artefacts so I will not try use this nomodeset option anymore.

Maybe you can help me?

EDIT: I found Bug #1838644 and I have this same problem like more users in the past. I am on 5.4.0-66 kernel like you can see above.

Some people wrote that migration to xrender helps so how I can do this on the GNOME environment? I must install something?