[JoelEinbinder]

You can set `pipe` to true in puppeteer (default false) here https://pptr.dev/api/puppeteer.launchoptions

By default, Playwright launches this way and you have to specifically enable the tcp listening.

[jesprenj]

Great, I stand corrected! I still don't know how they convince firefox/chromium to use a pipe as a websocket transport layer.