Does it do this in Altium 19? Altium 20 is in beta phase, so use at your own risk. Even soon after it is released, there is elevated risk for a while.
You did not state how Altium crashes. If it shows a small screen with memory violation errors, it is an Altium problem. If Altium hangs, it is an Altium problem. If Altium just disappears off screen, it is an Altium problem.