diff --git a/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.cpp b/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.cpp
index 7a4bea157a..bd21e60034 100644
--- a/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.cpp
+++ b/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.cpp
@@ -10,7 +10,7 @@
 namespace Web::IntersectionObserver {
 
 // https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-intersectionobserver
-NonnullRefPtr<IntersectionObserver> IntersectionObserver::create_with_global_object(JS::GlobalObject& global_object, JS::Value callback, IntersectionObserverInit const& options)
+NonnullRefPtr<IntersectionObserver> IntersectionObserver::create_with_global_object(JS::GlobalObject& global_object, Bindings::CallbackType const& callback, IntersectionObserverInit const& options)
 {
     // FIXME: Implement
     (void)global_object;
diff --git a/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.h b/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.h
index 122db71c96..0edc146398 100644
--- a/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.h
+++ b/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.h
@@ -25,7 +25,7 @@ class IntersectionObserver
 public:
     using WrapperType = Bindings::IntersectionObserverWrapper;
 
-    static NonnullRefPtr<IntersectionObserver> create_with_global_object(JS::GlobalObject&, JS::Value callback, IntersectionObserverInit const& options = {});
+    static NonnullRefPtr<IntersectionObserver> create_with_global_object(JS::GlobalObject&, Bindings::CallbackType const& callback, IntersectionObserverInit const& options = {});
 
     void observe(DOM::Element& target);
     void unobserve(DOM::Element& target);
diff --git a/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.idl b/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.idl
index c5d2a4bbfc..1cc24b6a93 100644
--- a/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.idl
+++ b/Userland/Libraries/LibWeb/IntersectionObserver/IntersectionObserver.idl
@@ -1,10 +1,11 @@
 #import <DOM/Element.idl>
 #import <DOM/Node.idl>
 
+callback IntersectionObserverCallback = undefined (sequence<IntersectionObserverEntry> entries, IntersectionObserver observer);
+
 [Exposed=(Window)]
 interface IntersectionObserver {
-    // FIXME: Should be: IntersectionObserverCallback
-    constructor(any callback, optional IntersectionObserverInit options = {});
+    constructor(IntersectionObserverCallback callback, optional IntersectionObserverInit options = {});
 
     undefined observe(Element target);
     undefined unobserve(Element target);