That's interesting... Have you tried rebooting your device entirely?
Do you have shell access? Having a look at the logs might be insightful

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I'm away right now, so I can't build another release until a few days, but it might not be needed, as there is a genuine quirk related to the Kobo update process that means it may take an extra reboot for KFMon to actually start. Hence my "try a full reboot first" answer

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