The extension takes Vite's WebSocket port, and currently Vite when run in middleware mode doesn't adapt, so HMR fails

[silvenon]

I don't consider this to be a bug of the extension, but because the extension is taking the port all of the time, regardless of whether the tests are running or not, I thought you should be aware of it. vitejs/vite#14328

WebSocket server error: Port is already in use

It may be a bit difficult to figure out for someone who's taking the port, so I wanted to cross-link the two projects. It's ultimately on Vite to reach a conclusion, but in order to enjoy this extension people I think thave to hard code some HMR port if they're creating Vite server in middleware mode, by using server.hmr.port.

Vite CLI doesn't have this problem.

[sheremet-va]

This extension always starts a Vite server in middleware mode. The problem is that Vite also always starts a websocket connection even when it's not used (Vitest disables HMR).

[silvenon]

Ah, I see! That's a tough one, either way a problem upstream. Thankfully only a bummer when not using Vite CLI.