FIX: If a topic/post cannot be oneboxed, don't swallow the href.

lib/oneboxer/discourse_local_onebox.rb

@@ -28,12 +28,13 @@ def onebox
 
         @template = 'user'
       when 'topics'
+
+        linked = "<a href='#{@url}'>#{@url}</a>"
         if route[:post_number].present? && route[:post_number].to_i > 1
           # Post Link
           post = Post.where(topic_id: route[:topic_id], post_number: route[:post_number].to_i).first
-          return nil unless post
-
-          return @url unless Guardian.new.can_see?(post)
+          return linked unless post
+          return linked unless Guardian.new.can_see?(post)
 
           topic = post.topic
           slug = Slug.for(topic.title)
@@ -50,9 +51,8 @@ def onebox
         else
           # Topic Link
           topic = Topic.where(id: route[:topic_id].to_i).includes(:user).first
-          return nil unless topic
-
-          return @url unless Guardian.new.can_see?(topic)
+          return linked unless topic
+          return linked unless Guardian.new.can_see?(topic)
 
           post = topic.posts.first