It’s too bad that history doesn’t record online and offline events. I get push notifications, but that’s not very helpful.
I remember a few years ago the battery level vanished from the history. The impression I formed then was that there was a move towards separating out the health metadata for a device. If so not a lot came of it for the end users, though the client API does include the health diagnostics for devices which seems to include a history of sorts for offline events.
Given that it is possible to for apps to subscribe to online/offline events I’ve always been a little surprised that the ability to trigger on online/offline events never found it’s way into the Rules API (or more likely into the version of Rules powering Routines since those seem to hold sway these days).
FYI, I was a strong supporter of health events for routines while I worked there. I wasn’t able to get that feature off the ground.
I find it rather ironic that, with the exception of hubs where you might eventually get a push notification, the only way your attention is drawn to devices being offline is if you happen to open the mobile app on specific pages. At that point you are then in the only place that sees offline as an absolute fact rather than a suspicion and then disables the device controls that might fix the issue.
I have an IKEA water leak sensor with long sleep cycles that goes offline/online frequently. I get push notifications multiple times a day, even when I don’t have the ST app open. I’ve sent a couple of hub logs, and there’s progress so far.
It looks like a Zigbee offline fix is in the works. I don’t know if will fix the Matter device issue (IKEA water leak).
Firmware 61.6 made Zigbee offline issues worse no better.