Allow reports with long comments from remote instances, but truncate (#25028)

app/lib/activitypub/activity/flag.rb

@@ -16,7 +16,7 @@ class ActivityPub::Activity::Flag < ActivityPub::Activity
         @account,
         target_account,
         status_ids: target_statuses.nil? ? [] : target_statuses.map(&:id),
-        comment: @json['content'] || '',
+        comment: report_comment,
         uri: report_uri
       )
     end
@@ -35,4 +35,8 @@ class ActivityPub::Activity::Flag < ActivityPub::Activity
   def report_uri
     @json['id'] unless @json['id'].nil? || invalid_origin?(@json['id'])
   end
+
+  def report_comment
+    (@json['content'] || '')[0...5000]
+  end
 end

app/lib/activitypub/tag_manager.rb

@@ -27,6 +27,8 @@ class ActivityPub::TagManager
     when :note, :comment, :activity
       return activity_account_status_url(target.account, target) if target.reblog?
       short_account_status_url(target.account, target)
+    when :flag
+      target.uri
     end
   end
 
@@ -41,6 +43,8 @@ class ActivityPub::TagManager
       account_status_url(target.account, target)
     when :emoji
       emoji_url(target)
+    when :flag
+      target.uri
     end
   end