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ok, sorry for that. I’m not so familiar with this proceed at the moment. I used the first on and yes that’s the beta version. I will use the last official one and try it again. Thanks for help.

OK, but I dont find this version number on unity store. Do you mean 2020.3.15f2 (from 27 Jul, 2021)?

I thought I used the current LTS Release 2020.3.33f1 from this page: https://unity3d.com/unity/qa/lts-releases?version=2020.3&page=1

How do I see that this 33f1 is a beta version and whats the last official version? 

In the "Scripting Define Symbols where nothing.

I added this two scripts but it didnt change anything. The tabe has only one entry and the Safe Mode starts again.

Thanks, the "specially active input" was the problem.