if anybody use linux *ubunt flavor there is a solution for the problem. it looks like that upgrading ubuntu to 20.04 removes python3-lhafile package.
if you have the fs-use ppa for ubuntu enabled just install it via apt install python3-lhafule
if oyu haven't enabled the ppa on your system go here:
https://fs-uae.net/download#ubuntu
and follow the instructions after doing so get python3-lhafile with apt install python3-lhafile
afterwards do a file database scan and voila all whdload installs are back again.
for other linux flavors check the link for how to do it on your used distro.