Since unityhub 3.x you can only get it from unity's package manager repos. The appimage is stuck at 2.x desyncing versions between linux and windows/macos.
An alternative would be to just download it using apt: https://docs.unity3d.com/hub/manual/InstallHub.html#install-hub-linux
Since unityhub 3.x you can only get it from unity's package manager repos. The appimage is stuck at 2.x desyncing versions between linux and windows/macos. An alternative would be to just download it using apt: https://docs.unity3d.com/hub/manual/InstallHub.html#install-hub-linux