Server Version#: 1.25.4.5487
Player Version#: 4.73.3 (Win11), 5.0.1 (LG webOS)
I rolled back to 1.25.3.5409 and all connectivity was re-established. I have not made any changes to settings or router. All devices on the same network. My TV (LG 42LB6300, webOS 1.4.0-2533 afro-ashley) could not connect at all on the latest server version (above), and laptop (also Win11, running the same web app version as the server PC, via firefox) can only connect via relay.
As a side-note, I tried to connect remotely from a newer LG TV (to 1.25.3.5409), but that one couldn’t connect at all either, though that is likely a separate issue. Xplay worked, but I don’t like its interface, or having to pay for it, or its limitations (max 12 bonus features, for instance). It worked on prior versions, but both the server and the app have been updated several times since I last tried it.