diff -up chromium-122.0.6261.69/third_party/pdfium/core/fxcrt/fx_memory_wrappers.h.me chromium-122.0.6261.69/third_party/pdfium/core/fxcrt/fx_memory_wrappers.h
--- chromium-122.0.6261.69/third_party/pdfium/core/fxcrt/fx_memory_wrappers.h.me	2024-02-24 13:02:58.931586003 +0100
+++ chromium-122.0.6261.69/third_party/pdfium/core/fxcrt/fx_memory_wrappers.h	2024-02-24 13:03:33.152251546 +0100
@@ -82,6 +82,7 @@ struct FxPartitionAllocAllocator {
   }
 
   // There's no state, so they are all the same,
+  bool operator==(const FxPartitionAllocAllocator&) const { return true; }
   bool operator==(const FxPartitionAllocAllocator& that) { return true; }
   bool operator!=(const FxPartitionAllocAllocator& that) { return false; }
 };