I’m no longer using Brave, but I only had the issue happen a couple of times, then never again.
Your sticking to longpoll issue sounds like something I’ve experienced (with chrome). I posted about it here LiveView falls back to longpoll after dev server restart
Basically, websocket is used in dev environment until I kill the dev server and restart. After that any existing browser tabs connected to the server will use longpoll, but new browser sessions use websocket.
