Don't expose remote accounts to search engines

lib/pleroma/formatter.ex

@@ -34,10 +34,12 @@ defmodule Pleroma.Formatter do
         ap_id = get_ap_id(user)
         nickname_text = get_nickname_text(nickname, opts)
 
+        rel = if user.local, do: "ugc", else: "ugc canonical"
+
         link =
-          ~s(<span class="h-card"><a data-user="#{id}" class="u-url mention" href="#{ap_id}" rel="ugc">@<span>#{
+          ~s(<span class="h-card"><a data-user="#{id}" class="u-url mention" href="#{ap_id}" rel="#{
-            nickname_text
+            rel
-          }</span></a></span>)
+          }">@<span>#{nickname_text}</span></a></span>)
 
         {link, %{acc | mentions: MapSet.put(acc.mentions, {"@" <> nickname, user})}}
 

priv/scrubbers/default.ex

@@ -26,7 +26,8 @@ defmodule Pleroma.HTML.Scrubber.Default do
     "nofollow",
     "noopener",
     "noreferrer",
-    "ugc"
+    "ugc",
+    "ugc canonical"
   ])
 
   Meta.allow_tag_with_these_attributes(:a, ["name", "title"])

priv/scrubbers/links_only.ex

@@ -19,7 +19,8 @@ defmodule Pleroma.HTML.Scrubber.LinksOnly do
     "noopener",
     "noreferrer",
     "me",
-    "ugc"
+    "ugc",
+    "ugc canonical"
   ])
 
   Meta.allow_tag_with_these_attributes(:a, ["name", "title"])

priv/scrubbers/twitter_text.ex

@@ -26,7 +26,9 @@ defmodule Pleroma.HTML.Scrubber.TwitterText do
     "tag",
     "nofollow",
     "noopener",
-    "noreferrer"
+    "noreferrer",
+    "ugc",
+    "ugc canonical"
   ])
 
   Meta.allow_tag_with_these_attributes(:a, ["name", "title"])

test/formatter_test.exs

@@ -173,7 +173,7 @@ defmodule Pleroma.FormatterTest do
       expected_text =
         ~s(<span class="h-card"><a data-user="#{mike.id}" class="u-url mention" href="#{
           mike.ap_id
-        }" rel="ugc">@<span>mike</span></a></span> test)
+        }" rel="ugc canonical">@<span>mike</span></a></span> test)
 
       assert expected_text == text
     end

test/user_test.exs

@@ -1411,7 +1411,7 @@ defmodule Pleroma.UserTest do
       expected_text =
         ~s(A.k.a. <span class="h-card"><a data-user="#{remote_user.id}" class="u-url mention" href="#{
           remote_user.ap_id
-        }" rel="ugc">@<span>nick@domain.com</span></a></span>)
+        }" rel="ugc canonical">@<span>nick@domain.com</span></a></span>)
 
       assert expected_text == User.parse_bio(bio, user)
     end