Big Sur first impression

Hello,

My experience is frustrating, as I can’t even manage to install BS on a VM on my main computer.
With Parallels Desktop 15 (same behaviour with VirtualBox), as soon as the VM is waiting for inputs, nothing works. The mouse won’t move, the keyboard won’t do anything; the VM has the focus correctly put into.

On another computer, I’ve successfully installed a BS VM (but there are only 4 GB of RAM on the host). If I bring this VM to my main Mac, the same input problem happens again.
Starting the VM in verbose mode, I’m seeing lines stating HIDD has been killed by another process (I have only the pid, so I can’t guess what happens there). Obviously, since HIDD manages all the inputs, this is what cause the issue I’m having.

If I start in safe mode (or, also, single user mode), the problem is gone; the mouse and keyboard work and I can install the VM. But as soon as I remove the flags telling to start “abnormally”, I can’t use the VM again.

I’ve tried changing a lot of settings in the VM’s configuration, but I don’t have a step-by-step guide or clue (only trying things in random orders).

Nothing helpful in my searches. Posted in Parallels forum and Xojo’s forum but no helpful answer either.

It seems I’m the “only one” having this issue; my concern is, in that case, the problem will fairly well never be addressed if no one (Parallels inc., Apple) knows about it, or seems to care for it.

If someone here has an idea, I’d love to hear it.