Today I upgraded my test environment to V12 and by now everything´s running very fine !
The first you’ll see are the new icons on your desktop indicating that V12 is installed:

Also the splash screen of the HCL Notes V12 Beta 1 client is looking a little bit more up-to-date
than the old one:

Take a look what you can expect in HCL Notes V12: https://bit.ly/36bzGfh