Live reload randomly failing

The cause is completely unclear to me… the server will run fine for a while then the below happens. I thought it was related to the ETS session store and multiple tabs. The reason is at least in one instance having multiple tabs open all would fail but one.

15:34:20.822 [error] Ranch listener ClientWeb.Endpoint.HTTP had connection process started with :cowboy_clear:start_link/4 at #PID<0.236511.0> exit with reason: {%ArgumentError{message: "no socket supervision tree found for Phoenix.LiveReloader.Socket.\n\nEnsure your ClientWeb.Endpoint contains a socket mount, for example:\n\n    socket \"/socket\", Phoenix.LiveReloader.Socket,\n      websocket: true,\n      longpoll: true\n"}, [{Phoenix.Socket.PoolSupervisor, :start_child, 3, [file: ~c"lib/phoenix/socket/pool_supervisor.ex", line: 23]}, {Phoenix.Channel.Server, :join, 4, [file: ~c"lib/phoenix/channel/server.ex", line: 28]}, {Phoenix.Socket, :handle_in, 4, [file: ~c"lib/phoenix/socket.ex", line: 665]}, {WebSockAdapter.CowboyAdapter, :websocket_handle, 2, [file: ~c"lib/websock_adapter/cowboy_adapter.ex", line: 24]}, {:cowboy_websocket, :handler_call, 6, [file: ~c"/home/user/Documents/sever/deps/cowboy/src/cowboy_websocket.erl", line: 528]}, {:cowboy_http, :loop, 1, [file: ~c"/home/user/Documents/sever/deps/cowboy/src/cowboy_http.erl", line: 253]}, {:proc_lib, :init_p_do_apply, 3, [file: ~c"proc_lib.erl", line: 241]}]}