Long waits when roaming between APs on my LAN

I recently changed phone (Pixel 11), reinstalled the companion app and everything works as expected. Except that I’m now experiencing longs waits (5-10s displaying the screenshot below) every time I launch the app after roaming between APs on my LAN:

This was not happening with my old Pixel phone.
App config is as follow:

If I leave the internal URL blank (and I always connect through Nabu Casa) I see no noticeable delays when starting the app.

I have a valid (CA signed) *.mydomain.com certificate installed, my gateway is a Ubiquiti UDM-SE (with a split DNS), and the APs are Ubiquiti U6-Pro.

I tried to stop WebView on my Pixel and clear its cache (as suggested on other threads), to no avail. Any idea what else could be causing this problem?


Home Assistant OS (running in a Proxmox VM)
Core 2026.9.4
Supervisor 2026.09.3
Operating System 18.3
Frontend 20260826.7
Mobile App: 2026.8.4-full