This started happening a few months ago, I would be minding my own Ubuntu business and then suddenly I can’t left click.
After much digging and stupid AI querying, I added something to disabled power management to my boot sequence. That seems to minimize the problems but I still get the problem every 5 minutes or so.
To temporarily fix the problem I Ctrl-alt F3 then F2 to come back to. GNOME.
I tried with a mint usb and I got the same problem. I thought it was then maybe a mouse problem but the pointer does the same no matter what mouse I use and every mouse I tested worked fine on another Ubuntu of the same release. So I think maybe it is some sort of hardware and driver combination and to power management.
I see lots of posts of past years but nothing more recently, but no real solutions or explanations for what might be happening.
Could be the USB controller. I’ve had pretty terrible USB problems with certain AMD systems. Typically only with high-bandwidth applications, but I know some people have had problems even with peripherals like mice.
Its a weird problem. But I think it’s not just the mouse. It could be other stuff USB. You could be right. I will check with Windows 10 (garbage on a second boot drive)
Also look in your bios.
Barring that, yeah checking a different OS is another good step.