The Linux 5.4 (LTS!) and 5.5 releases had consistent hangs on many Intel GPUs that use the i915 driver. I had to revert back to 4.19.x on my Linux machine.

https://linuxreviews.org/Linux_Kernel_5.5_Will_Not_Fix_The_F...

They should be fixed by now, but basically the latest LTS kernel was broken for 3-4 months on many Intel GPUs.