iOS - transitioning from wifi to cellular seems to lose DNS

Running 1.8.0 on iOS:

  1. Start being connected to wifi with Tailscale enabled, everything works fine
  2. Disconnect from wifi (i.e. now I’m on cellular), with Tailscale still enabled - at this point, when you type a website URL into Safari it just gets stuck and doesn’t load.
  3. Turn off Tailscale or reconnect to wifi - now websites will load again.

Magic DNS is currently disabled, but I did have it enabled at some point. Also my cellular carrier is T-Mobile which suffers from this issue which I guess could possibly be related

I had Magic DNS disabled in my admin console, but I still had nameservers listed - deleting them seems to have fixed this. So something weird appears to be happening when Magic DNS is disabled but with nameservers listed.

I had the same problem. (android 11, T-Mobile cell and home internet)
eventually it went away when I upgraded to ver 1.9.44 on windows 10, and latest ver on f-droid.
also I set up dnsmasq on my router, added the router ip and 1.1.1.1 as nameservers, and enabled MagicDNS.

now everything seems to work (mostly)