Samsung Galaxy S20 - app bad

I was told to clear the cache and data, install power cycle and reinstall. After repeating the steps 14 times it worked and then later the issue recurred.

The same problem since 4th Dec. 2020 - with Samsung Galaxy S20 Ultra 5G chess.com App is no longer usable.
Enabling "full screen mode" in my case doesn't help at all.
I've reported this issue to help service of chess.com - it's been confirmed, that the problem is with new system shell from Samsung - OneUI 3.0.
The programmers are working on solution, I've been informed.
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