diff --git a/Userland/Libraries/LibWeb/HTML/Window.cpp b/Userland/Libraries/LibWeb/HTML/Window.cpp
index 7850264d83d..28667ca2be5 100644
--- a/Userland/Libraries/LibWeb/HTML/Window.cpp
+++ b/Userland/Libraries/LibWeb/HTML/Window.cpp
@@ -594,6 +594,21 @@ WebIDL::ExceptionOr<JS::NonnullGCPtr<Storage>> Window::session_storage()
     return JS::NonnullGCPtr { *storage };
 }
 
+// https://html.spec.whatwg.org/multipage/interaction.html#sticky-activation
+bool Window::has_sticky_activation() const
+{
+    // When the current high resolution time given W
+    auto current_time = HighResolutionTime::current_high_resolution_time(*this);
+
+    // is greater than or equal to the last activation timestamp in W
+    if (current_time >= m_last_activation_timestamp) {
+        // W is said to have sticky activation.
+        return true;
+    }
+
+    return false;
+}
+
 // https://html.spec.whatwg.org/multipage/interaction.html#transient-activation
 bool Window::has_transient_activation() const
 {
diff --git a/Userland/Libraries/LibWeb/HTML/Window.h b/Userland/Libraries/LibWeb/HTML/Window.h
index 1b4b23534b1..1ac16f4dbef 100644
--- a/Userland/Libraries/LibWeb/HTML/Window.h
+++ b/Userland/Libraries/LibWeb/HTML/Window.h
@@ -116,6 +116,9 @@ public:
 
     AnimationFrameCallbackDriver& animation_frame_callback_driver() { return m_animation_frame_callback_driver; }
 
+    // https://html.spec.whatwg.org/multipage/interaction.html#sticky-activation
+    bool has_sticky_activation() const;
+
     // https://html.spec.whatwg.org/multipage/interaction.html#transient-activation
     bool has_transient_activation() const;