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diff --git a/lib/pleroma/web/shout_channel.ex b/lib/pleroma/web/shout_channel.ex
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+++ b/lib/pleroma/web/shout_channel.ex
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+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.ShoutChannel do
+  use Phoenix.Channel
+
+  alias Pleroma.User
+  alias Pleroma.Web.MastodonAPI.AccountView
+  alias Pleroma.Web.ShoutChannel.ShoutChannelState
+
+  def join("chat:public", _message, socket) do
+    send(self(), :after_join)
+    {:ok, socket}
+  end
+
+  def handle_info(:after_join, socket) do
+    push(socket, "messages", %{messages: ShoutChannelState.messages()})
+    {:noreply, socket}
+  end
+
+  def handle_in("new_msg", %{"text" => text}, %{assigns: %{user_name: user_name}} = socket) do
+    text = String.trim(text)
+
+    if String.length(text) in 1..Pleroma.Config.get([:shout, :limit]) do
+      author = User.get_cached_by_nickname(user_name)
+      author_json = AccountView.render("show.json", user: author, skip_visibility_check: true)
+
+      message = ShoutChannelState.add_message(%{text: text, author: author_json})
+
+      broadcast!(socket, "new_msg", message)
+    end
+
+    {:noreply, socket}
+  end
+end
+
+defmodule Pleroma.Web.ShoutChannel.ShoutChannelState do
+  use Agent
+
+  @max_messages 20
+
+  def start_link(_) do
+    Agent.start_link(fn -> %{max_id: 1, messages: []} end, name: __MODULE__)
+  end
+
+  def add_message(message) do
+    Agent.get_and_update(__MODULE__, fn state ->
+      id = state[:max_id] + 1
+      message = Map.put(message, "id", id)
+      messages = [message | state[:messages]] |> Enum.take(@max_messages)
+      {message, %{max_id: id, messages: messages}}
+    end)
+  end
+
+  def messages do
+    Agent.get(__MODULE__, fn state -> state[:messages] |> Enum.reverse() end)
+  end
+end