LibreOffice doesn't launch on my Windows 10 Pro 64bit

I’ve upgraded my old LO 5.x installation to version and it stopped to launch completely. Re-installation did not help. New installation of the version did not help.
The application shows just the “LibreOffice The Document Foundation” banner for an ‘endless’ time and the LibreOffice process in the task manager shows quite high consumption of processor power.
I’m running Windows 10 Pro 64bit with the latest patches as of April 20th, 2019.
Any idea what I should do?

Check the FAQ by @mikekaganski

Thanks for that link. However it doesn’t seem to be related to my problem. Actually I did not encounter any problems while installing the LO