Win 11/LRT 7.2
It does not show an icon in the Windows Task Bar - just a white sheet - see attachment

I can not reproduce it. Sometimes Windows Icon cache goes cracy. Maybe update to beta 3.

Beta 3 does not make any difference.

As said, I didnt see this with beta 2 nor with beta 3. It is definitely not an issue of LRT. I assume you restarted your PC.
What you can do is to clear the Windows Icon cache. There are many tutorials on the web how to do.

This happened, when a previous license was not full uninstalled. This should be fixed in beta 4.