Comment # 18 on bug 1218274 from Peter Küppers

(In reply to Peter Küppers from comment #10)
> KRDC which uses freerdp is also effected
> parameter /gfx on command line with xfreerdp didn't help for me (connecting
> to Windows 10 64bit running in Virtualbox on openSUSE 15.5 server) 
> downgrading to freerdp 2.4.0 Release 150400.3.20.1 helped

With the last update resp. patch from openSUSE 15.5 it seems to work for me
now.
New version is freerdp 2.4.0 Release 150400.3.32.1
Thanks a lot for everybody who was involved in the solution!