First, some background: I have a large number of OSes installed on removable storage, and I plug-in whichever distro I want to boot on my laptop on any given day. They run the gamut: Fedora, openSUSE, Kubuntu, Manjaro, Solus, Zorin, and even Windows To Go. (no Slackware...yet. they really need to release v15 already!) I have Hibernate working on most of them; only Solus and Zorin are giving me trouble. Obviously I'm not going to ask about Solus here, so the problem I'm having with Zorin is:
It Hibernates and then shuts off correctly, but when it Resumes from the hibernation data stored in its own dedicated swap partition, the OS grinds to a halt after it reloads the desktop. The mouse won't move, the keyboard won't type, nothing happens until I reboot my laptop. Even stranger, this happens when I Resume from Sleep mode as well -- where the RAM isn't written to the swap partition and the computer never completely turns off.
This makes me think one of the hardware devices in my laptop isn't behaving well when Zorin finishes resuming, but as I mentioned at the beginning, I have Hibernate working fine with several other distros. So there must be some incompatibility between my laptop and Zorin specifically. I don't know what that might be, though, especially since Kubuntu can Hibernate and Resume perfectly, and Zorin is built on Ubuntu. Could it be caused by something out-of-date in the 20.04 Focal Fossa code that Zorin is still using alongside the much-newer 5.11 kernel? Or is this a known problem caused by something else? I'm stumped at this point.