diff --git a/Userland/Libraries/LibWeb/WebIDL/Buffers.h b/Userland/Libraries/LibWeb/WebIDL/Buffers.h
index bfc07c0a0e8..c1949f5a15e 100644
--- a/Userland/Libraries/LibWeb/WebIDL/Buffers.h
+++ b/Userland/Libraries/LibWeb/WebIDL/Buffers.h
@@ -10,6 +10,7 @@
 #include <AK/Variant.h>
 #include <LibJS/Forward.h>
 #include <LibJS/Heap/Cell.h>
+#include <LibJS/Heap/CellAllocator.h>
 
 namespace Web::WebIDL {