Odd "ignoring unmatched topic" warning

I’m getting an odd error in which a topic from another phoenix project is the subject of an unmatched topic warning when I start the phoenix server of a new phoenix project.

Below is the code for the user_socket.ex of the new phoenix project.

defmodule HelloWeb.UserSocket do
  use Phoenix.Socket

  ## Channels
  # channel "room:*", HelloWeb.RoomChannel

  # Socket params are passed from the client and can
  # be used to verify and authenticate a user. After
  # verification, you can put default assigns into
  # the socket that will be set for all channels, ie
  #     {:ok, assign(socket, :user_id, verified_user_id)}
  # To deny connection, return `:error`.
  # See `Phoenix.Token` documentation for examples in
  # performing token verification on connect.
  def connect(_params, socket, _connect_info) do
    {:ok, socket}

  # Socket id's are topics that allow you to identify all sockets for a given user:
  #     def id(socket), do: "user_socket:#{socket.assigns.user_id}"
  # Would allow you to broadcast a "disconnect" event and terminate
  # all active sockets and channels for a given user:
  #     HelloWeb.Endpoint.broadcast("user_socket:#{user.id}", "disconnect", %{})
  # Returning `nil` makes this socket anonymous.
  def id(_socket), do: nil

One can see that I have not yet written in any channel specifications.

Here are the warnings

you probably have a browser tab open from other project that then tries to reconnect to the new project…

probably best/easiest to use different ports for the projects…


Thanks for that tip, I actually think it had something to do with the naming of the folder that held the project folder, there was spacing in the folder name and I think that caused some weird stuff to happen. When I changed the folder name (replacing space with underscore, _) and deleted then remade the project the problem was gone.

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