Add class=attachment to attachment links.

lib/pleroma/web/twitter_api/twitter_api.ex

@@ -35,7 +35,7 @@ defmodule Pleroma.Web.TwitterAPI.TwitterAPI do
   def add_attachments(text, attachments) do
     attachment_text = Enum.map(attachments, fn
       (%{"url" => [%{"href" => href} | _]}) ->
-        "<a href='#{href}'>#{href}</a>"
+        "<a href='#{href}' class='attachment'>#{href}</a>"
       _ -> ""
     end)
     Enum.join([text | attachment_text], "<br>")

test/web/twitter_api/twitter_api_test.exs

@@ -33,7 +33,7 @@ defmodule Pleroma.Web.TwitterAPI.TwitterAPITest do
 
     { :ok, activity = %Activity{} } = TwitterAPI.create_status(user, input)
 
-    assert get_in(activity.data, ["object", "content"]) == "Hello again, <a href='shp'>@shp</a>.<br>This is on another line.<br><a href='http://example.org/image.jpg'>http://example.org/image.jpg</a>"
+    assert get_in(activity.data, ["object", "content"]) == "Hello again, <a href='shp'>@shp</a>.<br>This is on another line.<br><a href='http://example.org/image.jpg' class='attachment'>http://example.org/image.jpg</a>"
     assert get_in(activity.data, ["object", "type"]) == "Note"
     assert get_in(activity.data, ["object", "actor"]) == user.ap_id
     assert get_in(activity.data, ["actor"]) == user.ap_id