--- a/net/minecraft/core/Holder.java
+++ b/net/minecraft/core/Holder.java
@@ -230,7 +_,7 @@
         }
 
         void bindTags(Collection<TagKey<T>> tags) {
-            this.tags = Set.copyOf(tags);
+            this.tags = it.unimi.dsi.fastutil.objects.ReferenceSets.unmodifiable(new it.unimi.dsi.fastutil.objects.ReferenceOpenHashSet<>(tags)); // Paper - use reference set because TagKey are interned
         }
 
         @Override
