I've recently converted from a VirtualBox/Vagrant setup on a MacOSX host (MacBook Pro Intel 32GB) where I was performing development in VSCode via SSH into a headless Ubuntu 18.04 VM. Now I'm using Parallels Pro with an Ubuntu 22.04 VM running Regolith as the desktop environment and I'm now performing dev work inside the VM itself rather than over SSH. For the most part performance in this new UI based setup has been fine as I'm using Neovim now instead of a heavy IDE like VSCode as before.
The problem now is that graphical apps like Firefox are so slow to render that they're effectively unusable. In addition, in any circumstance mouse lag is so great that it's required a lot of getting used to.
The GUI slowness is likely caused by the laptop being used in clamshell mode with two 2.5K monitors connected to it as well as a strange issue where the only resolution and scaling mode that makes the VM not blurry is 5K at 200% scaling. Any other combination is crusty.
The mouse lag I believe is a known issue concerning changes made to internal GUI rendering that have yet to be fully resolved.
I'm wondering if there are solutions out there for running this GUI at a more reasonable resolution so the hardware is not a strained and if there are solutions for the mouse rendering problem that I may have missed.