diff --git a/Userland/Libraries/LibWeb/Forward.h b/Userland/Libraries/LibWeb/Forward.h
index 1c0fe9a44a..9f75d87867 100644
--- a/Userland/Libraries/LibWeb/Forward.h
+++ b/Userland/Libraries/LibWeb/Forward.h
@@ -598,6 +598,7 @@ class ReadableStreamBYOBRequest;
 class ReadableStreamDefaultController;
 class ReadableStreamDefaultReader;
 class ReadableStreamGenericReaderMixin;
+class ReadIntoRequest;
 class ReadRequest;
 class TransformStream;
 class TransformStreamDefaultController;