i have noticed a huge improvement in my Zigbee devices since getting the 19.x firmware. I was fine until 18.22 was pushed out and almost daily, several of my zigbee devices would become unavailable (yes, I have device health enabled). Some of the devices would eventually come back online while some, I would have to remove the battery to get it back online. But since 19.x, I have only had one device become unavailable but it reconnected after awhile. Overall, I must say this is a huge improvement for my hub.
I have always been happy with both my zigbee and z-wave networks, but this update has made them both noticeably better. I’ve been looking for issues to provide feedback on this update but it has been great so far.
Yeah, one of my most notorious zigbee items – the samsung multisensor on the garage door – was going offline every 3-4 days, so much that I just gave up reseating the battery. I reseated the battery when this firmware came out and so far it hasn’t dropped after 5~ days.
As an update, the multisensor did drop after 14 days or so. However, after doing some investigation using FAQ: Mapping your ZigBee network with Digi's XCTU - I realized that the garage sensor is only able to mesh with 1 zigbee device (poorly at that) on my network to get back to the samsung hub.
So I’ll probably just add some random sensor in the garage to give it another device to mesh/bounce off.