Thread option just disappeared (3rd party BTR)

[rough pumice]

Decided to try thread, and since I had four Google 4K TV's, was experimenting with them. When I enable thread on them, it shows up in the Settings, Thread display, I picked one as default (leaving why there are multiple for another day), and tried adding a thread device (Heiman Smoke). Looked good, found it, set matter credentials, testing connectivity, adding to home assistant "Something went wrong". Tried a few times.

So I went back to Google home and added it there as a thread device. That worked fine, it communicated, shows up, works.

So I went back to HA and tried to link to it since it's now not new. That looked fine but timed out, would not link.

Decided to restart HA, restarted Matter add-on, restarted companion app... then I noticed the Thread option in setup is just gone.

If I try again to add the thread device it immediately says HA Server does not support thread. It apparently can no longer see the TV's (which have not changed). Rebooted (not just restarted) HA, same thing - thread is now just not shown at all.

Matter log shows nothing interesting, looks normal (I have no matter devices). Most guidance in docs is for USB/HA based Thread BR so not very helpful. Network is up, ipv6 addresses assigned to TV's and HA server, LAN passes multicast, if I go into the mDNS discovery in HA I see all the expected matter and related discovery for the TV's (well, all I know to expect). But again -- nothing in the TV's changed, it disappeared when HA rebooted (or something while I was restarting things).

The option in Settings is just gone... .any suggestions where to start?

HA is current 2026.2.3, sup 2026.02.3, os 17.1, running in HyperV VM with HAOS, no beta stuff just released code. On a reboot of HA the log errors (at the displayed level not detail) shows nothing that looks even vaguely related (a couple timeouts, a code depreciated in a different integration).

Suggestions?

[rough pumice]

Interesting aspect: I decided since I had no devices, to remove the matter integration, reboot (not just restart), add it back, reboot, and see if Thread appeared. It did not.

However, on a whim I used the companion app to try to add it. It tried -- it got to the adding to home assistant and failed after seeing the right thread border router (the TV). Just "Something went wrong". What's different now is if I go into google home and try to link to HA, it doesn't get far enough to show HA at all. So Google home thinks HA can't access a border router? Not sure, but a bit different. Still no "Thread" option under Settings.

[rough pumice]

So I managed to solve this sort of.... it turns out that "Thread" was in the ignored lists of devices. I didn't put it there. Really I didn't, I didn't even know it appeared there. Setting to not-ignored caused the menu option to come back.

Of course, it doesn't work. I had a conflict with google. Turned all the google's off, deleted that network, reset the new device as my preferred. Phone still wanted to use google. Had to clear data and cache on play services, reinstall companion app (I did, not sure if needed), reboot, and then sync under trouble shooting. That caused the companion app to use the right network.

But it still doesn't work -- it hangs on "Checking connectivity to ha-thread-b005" which is the right network. Sigh... need lunch and try again.