iOS 15.4: (very) major problems observed with Homebridge plugins

A little introductory reminder: Homebridge allows integration of smart home devices that do not natively support HomeKit. Currently, there are over 2,000 Homebridge plugins that support thousands of home automation accessories (Nest, Kasa TP-Link, Zigbee, Belkin Wemo, monQ, UniFi Protect, etc.).

Yes but here it isiOS 15.4 seems (sometimes) to break compatibility with Homebridge, as evidenced by numerous threads on Reddit. An user thus explains than “Since yesterday’s 15.4 update, Siri commands for these devices no longer work: I just get a response of ‘uh, oh there’s a problem’. A user this time shares her problem: “I have two houses set up, both with their own Raspberry Pi/w Homebridge and AppleTV hubs. After upgrading my iPhone to 15.4, all HB and Nest enabled lights are giving “Not Responding” error. In both houses, on iPhone via the HK app, Siri and on ATV – scenes will not work. My boyfriend who is still on 15.3 has no issues at all. Any ideas? ». And so it is on pages and Reddit talk pages.

Note all the same that the answers to these testimonials seem to indicate that not all users of Homebridge plugins are concerned by these compatibility concerns, which adds even more depth to this mystery. Finally, we note that in most problematic cases, reinstalling the system does not solve the problems observed. Apple has obviously been warned of these risky compatibilities, but has not yet reacted.

Thanks to our reader Polzy for the info