Some months back I did write about how to enable hibernation in Kubuntu as it is not enabled by default like it is in Debian. I have particularly noted that this is an issue on computers made by HP in that following the given instructions still does not make hibernation available in some HP manufactured computers. At time time of writing I have been able to confirm that both Windows 10 and Debian 11 are able to hibernate these computers and of note, neither of these operating systems requires any configuration by the user to make hibernation work. It can be expected that HP would have a different Bios spec to Gigabyte who make the mainboards of all my other computers that have no difficulty in hibernating with Kubuntu, but in this case it is implied there is some kind of difference in the Kubuntu kernel that happens when it boots on a HP device and may be due to a specific Bios setting. I will report back when I have discovered exactly what is going on.
UPDATE: The computer that would not hibernate had Secure Boot enabled. The assumption of Debian and Windows 10 being unaffected was erroneous as the computer they were tested on actually had Secure Boot already disabled. Although these systems are a bit tricky to configure, Secure Boot can be disabled and then hibernation will work exactly as expected. So that is pleasing as I was starting to think there would have been a problem with the configuration of Kubuntu itself when all that is needed is to change a Bios setting.