#306

backend/app/controllers/tags_controller.rb

@@ -379,12 +379,20 @@ class TagsController < ApplicationController
   end
 
   def visible_root_tag_ids graph
-    graph[:tags_by_id].filter_map do |tag_id, _attrs|
+    root_ids = Set.new
+
+    graph[:tags_by_id].each do |tag_id, attrs|
       next unless visible_root_tag?(tag_id, graph)
       next unless visible_subtree?(tag_id, graph)
 
-      tag_id
+      if attrs[:deprecated]
+        collect_visible_child_tag_ids(tag_id, graph, root_ids, Set.new)
+      else
+        root_ids << tag_id
+      end
     end
+
+    root_ids.to_a
   end
 
   def visible_root_tag? tag_id, graph