Maximilian Hils

#### Startup Hook I'm not sure if there's much of a use case outside of the proxyserver addon? Or differently, is there a plausible scenario why an addon other than...

> Did you see my comment on the original PR? [#5393 (comment)](https://github.com/mitmproxy/mitmproxy/pull/5393#issuecomment-1153666100) I know this is yet another discussion, but I just wanted to bring that up one last time....

> What keeps mitmweb from opening a WebSocket which would give you the current state and in the future all changes? Yes. The React code would/should do that, but then...

(@meitinger: sorry for derailing your PR discussion) > It looks like mitmweb fetches the current flows and then also opens a WebSocket (I assume that also opens a slight window...

> If the latter is desired, I can make the necessary changes in this PR. I don't think anyone has super strong opinions yet, so let's just keep things as-is...

> Not really, no. If we do [#5512 (comment)](https://github.com/mitmproxy/mitmproxy/pull/5512#issuecomment-1208270007) within `instance.stop()`, then yes. Starting might need a couple of msec, sometimes even a second... (Then again, we don't know what...

Yeah - raising in `__setattr__` is good, we need to fix `copy()` to not trigger that I think. :)

I haven't looked through `quic.py` yet, but everything else looks fantastic overall. 🍰 What's the reason for making `read()` return the address as well?

FYI, I have an experimental branch based on your work at https://github.com/meitinger/mitmproxy/compare/quic...mhils:mitmproxy:pr-5435. I hope I'll find some time over the weekend to continue, at least the weather looks promising. 🙃...

You should be able to see them. We'd need a clear minimal example that reproduces the issue.