FIX: remove ItemList schema from linkbacks in crawler view (#36608)

ZogStriP · web-flow · commit 58d298cae1cd · 2025-12-11T10:41:47.000+01:00
Linkbacks (reflection links showing "topics that link here") were
incorrectly using schema.org/ItemList markup. This caused Google Rich
Results Test errors ("Multiple ListItem elements defined on page") when
combined with plugins like discourse-ai that add their own ItemList for
related topics.

ItemList is intended for curated/ranked lists (e.g., "Related Topics").
Linkbacks are automatic citations, not recommendations, so plain links
are semantically correct.

Also extracts `linkbacks_for(post)` helper to TopicView for cleaner
template code.

Internal ref - t/170560
diff --git a/app/views/topics/show.html.erb b/app/views/topics/show.html.erb
@@ -108,18 +108,15 @@
               <span class='post-likes'><%= post.like_count > 0 ? t('post.has_likes', count: post.like_count) : '' %></span>
             </div>
 
-              <% if @topic_view.link_counts[post.id] && @topic_view.link_counts[post.id].filter { |l| l[:reflection] }.length > 0 %>
-                <div class='crawler-linkback-list' itemscope itemtype='http://schema.org/ItemList'>
-                  <% @topic_view.link_counts[post.id].each_with_index do |link, i| %>
-                    <% if link[:reflection] && link[:title].present? %>
-                      <div itemprop='itemListElement' itemscope itemtype='http://schema.org/ListItem'>
-                        <a itemprop='url' href="<%=link[:url]%>"><%=link[:title]%></a>
-                        <meta itemprop='position' content='<%= i+1 %>'>
-                      </div>
-                    <% end %>
+              <% if (linkbacks = @topic_view.linkbacks_for(post)).present? %>
+                <div class='crawler-linkback-list'>
+                  <% linkbacks.each do |link| %>
+                    <div>
+                      <a href="<%=link[:url]%>"><%=link[:title]%></a>
+                    </div>
                   <% end %>
                 </div>
-            <% end %>
+              <% end %>
 
             <%= build_plugin_html "server:topic-show-crawler-post-end", post: post %>
           </div>
diff --git a/lib/topic_view.rb b/lib/topic_view.rb
@@ -714,6 +714,10 @@ def link_counts
       )
   end
 
+  def linkbacks_for(post)
+    link_counts[post.id]&.select { |l| l[:reflection] && l[:title].present? }
+  end
+
   def pm_params
     @pm_params ||= TopicQuery.new(@user).get_pm_params(topic)
   end
diff --git a/spec/fixtures/onebox/discourse_topic.response b/spec/fixtures/onebox/discourse_topic.response
@@ -280,7 +280,7 @@ And that too in just over an year, way to go! [boom]">
             <meta itemprop="userInteractionCount" content="0" />
           </div>
 
-            <div class='crawler-linkback-list' itemscope itemtype='http://schema.org/ItemList'>
+            <div class='crawler-linkback-list'>
             </div>
 
     </div>
diff --git a/spec/fixtures/onebox/discourse_topic_reply.response b/spec/fixtures/onebox/discourse_topic_reply.response
@@ -272,7 +272,7 @@ And that too in just over an year, way to go! [boom]">
             <meta itemprop="userInteractionCount" content="0" />
           </div>
 
-            <div class='crawler-linkback-list' itemscope itemtype='http://schema.org/ItemList'>
+            <div class='crawler-linkback-list'>
             </div>
 
     </div>
diff --git a/spec/views/topics/show.html.erb_spec.rb b/spec/views/topics/show.html.erb_spec.rb
@@ -1,34 +1,31 @@
 # frozen_string_literal: true
 
-require "ostruct"
-
 RSpec.describe "topics/show.html.erb" do
-  fab!(:category)
-  fab!(:topic) { Fabricate(:topic, category: category) }
+  fab!(:topic) { Fabricate(:topic, category: Fabricate(:category)) }
 
-  it "add nofollow to RSS alternate link for topic" do
+  it "adds nofollow to RSS alternate link" do
     topic_view = OpenStruct.new(topic: topic, posts: [], crawler_posts: [])
     topic_view.stubs(:summary).returns("")
     view.stubs(:crawler_layout?).returns(false)
-    view.stubs(:url_for).returns("https://www.example.com/test.rss")
+    view.stubs(:url_for).returns("https://example.com/test.rss")
     view.instance_variable_set("@topic_view", topic_view)
     assign(:tags, [])
 
     render template: "topics/show", formats: [:html]
 
     expect(view.content_for(:head)).to match(
-      %r{<link rel="alternate nofollow" type="application/rss\+xml" title="[^"]+" href="https://www.example.com/test\.rss" />},
+      %r{<link rel="alternate nofollow" type="application/rss\+xml"},
     )
   end
 
-  it "adds structured data" do
+  it "renders linkbacks as plain links without ItemList schema" do
     view.stubs(:include_crawler_content?).returns(true)
     post = Fabricate(:post, topic: topic)
     TopicLink.create!(
       topic_id: post.topic_id,
       post_id: post.id,
       user_id: post.user_id,
-      url: "https://example.com/",
+      url: "https://example.com/linked",
       domain: "example.com",
       link_topic_id: Fabricate(:topic).id,
       reflection: true,
@@ -38,27 +35,25 @@
 
     render template: "topics/show", formats: [:html]
 
-    links_list = Nokogiri::HTML5.fragment(rendered).css(".crawler-linkback-list")
-    first_item = links_list.css('[itemprop="itemListElement"]')
-    expect(first_item.css('[itemprop="position"]')[0]["content"]).to eq("1")
-    expect(first_item.css('[itemprop="url"]')[0]["href"]).to eq("https://example.com/")
+    doc = Nokogiri::HTML5.fragment(rendered)
+    linkbacks = doc.css(".crawler-linkback-list")
+    expect(linkbacks.css("a[href='https://example.com/linked']")).to be_present
+    expect(linkbacks.css('[itemtype*="ItemList"]')).to be_empty
   end
 
-  it "uses comment scheme type for replies" do
+  it "uses DiscussionForumPosting with Comment schema for replies" do
     view.stubs(:crawler_layout?).returns(true)
     view.stubs(:include_crawler_content?).returns(true)
-    Fabricate(:post, topic: topic)
-    Fabricate(:post, topic: topic)
-    Fabricate(:post, topic: topic)
+    3.times { Fabricate(:post, topic: topic) }
     assign(:topic_view, TopicView.new(topic))
     assign(:tags, [])
 
     render template: "topics/show", formats: [:html]
 
     doc = Nokogiri::HTML5.fragment(rendered)
-    topic_schema = doc.css('[itemtype="http://schema.org/DiscussionForumPosting"]')
-    expect(topic_schema.size).to eq(1)
-    expect(topic_schema.css('[itemtype="http://schema.org/Comment"]').size).to eq(2)
-    expect(topic_schema.css('[itemprop="articleSection"]')[0]["content"]).to eq(topic.category.name)
+    posting = doc.css('[itemtype*="DiscussionForumPosting"]')
+    expect(posting.size).to eq(1)
+    expect(posting.css('[itemtype*="Comment"]').size).to eq(2) # replies only, not OP
+    expect(posting.css('[itemprop="articleSection"]').first["content"]).to eq(topic.category.name)
   end
 end
