Don't go through all available emoji.

object carry their emoji information.

lib/pleroma/formatter.ex

@@ -110,14 +110,10 @@ def parse_mentions(text) do
 
   @emoji @finmoji_with_filenames ++ @emoji_from_file
 
-  def emojify(text, additional \\ nil) do
-    all_emoji = if additional do
-      Map.to_list(additional) ++ @emoji
-    else
-      @emoji
-    end
-
-    Enum.reduce(all_emoji, text, fn ({emoji, file}, text) ->
+  def emojify(text, emoji \\ @emoji)
+  def emojify(text, nil), do: text
+  def emojify(text, emoji) do
+    Enum.reduce(emoji, text, fn ({emoji, file}, text) ->
       emoji = HtmlSanitizeEx.strip_tags(emoji)
       file = HtmlSanitizeEx.strip_tags(file)
       String.replace(text, ":#{emoji}:", "<img height='32px' width='32px' alt='#{emoji}' title='#{emoji}' src='#{MediaProxy.url(file)}' />")

lib/pleroma/web/twitter_api/representers/activity_representer.ex

@@ -145,7 +145,8 @@ def to_map(%Activity{data: %{"object" => %{"content" => content} = object}} = ac
       content
     end
 
-    html = HtmlSanitizeEx.basic_html(content) |> Formatter.emojify(object["emoji"])
+    html = HtmlSanitizeEx.basic_html(content)
+    |> Formatter.emojify(object["emoji"])
 
     %{
       "id" => activity.id,

lib/pleroma/web/twitter_api/views/activity_view.ex

@@ -37,7 +37,8 @@ def render("activity.json", %{activity: %{data: %{"type" => "Create", "object" =
       content
     end
 
-    html = HtmlSanitizeEx.basic_html(content) |> Formatter.emojify(object["emoji"])
+    html = HtmlSanitizeEx.basic_html(content)
+    |> Formatter.emojify(object["emoji"])
 
     %{
       "id" => activity.id,