Ok, it’s not a significant problem, but it ought to be an easy fix.
If I home the machine from a high Z position, it times out before reaching the endstop.
Communication timeout while idle, trying to trigger response from printer. Configure long running commands or increase communication timeout if that happens regularly on specific commands or long moves.
The cause is obvious: it just takes too long.
It isn’t a real problem: I can just hit ‘Home’ again, but it would be better to sort it…
And looking again, I think this is an Octoprint issue rather than Klipper, but hey ho…