Doesn't work as is, get "unable to join: unmatched topic" error

[ericridgeway]

You forgot the step where you need to change socket.js to use
let channel = socket.channel("room:lobby", {})
instead of
let channel = socket.channel("topic:subtopic", {})

[nelsonic]

@ericridgeway thank you for opening this issue! (glad someone was paying attention)
If you have time to create a pull request fixing the docs, please do.

[nelsonic]

I have added instructions to section 4.1: https://github.com/dwyl/phoenix-chat-example/tree/7a097643aa5b05e04321687ea6c169007a99e148#41-comment-out-lines-in-socketjs
so future learners/readers will not see the error.

@iteles please see: #33 (thanks!) 🌻