diff --git a/Libraries/LibWeb/DOM/Document.cpp b/Libraries/LibWeb/DOM/Document.cpp
index 3e5e356324f..b50382e01ab 100644
--- a/Libraries/LibWeb/DOM/Document.cpp
+++ b/Libraries/LibWeb/DOM/Document.cpp
@@ -505,7 +505,6 @@ void Document::visit_edges(Cell::Visitor& visitor)
     visitor.visit(m_document_observers);
     visitor.visit(m_pending_scroll_event_targets);
     visitor.visit(m_pending_scrollend_event_targets);
-    visitor.visit(m_intersection_observers);
     visitor.visit(m_resize_observers);
 
     visitor.visit(m_shared_resource_requests);
@@ -4037,7 +4036,14 @@ void Document::run_the_update_intersection_observations_steps(HighResolutionTime
     // 1. Let observer list be a list of all IntersectionObservers whose root is in the DOM tree of document.
     //    For the top-level browsing context, this includes implicit root observers.
     // 2. For each observer in observer list:
-    for (auto& observer : m_intersection_observers) {
+
+    // NOTE: We make a copy of the intersection observers list to avoid modifying it while iterating.
+    JS::MarkedVector<JS::NonnullGCPtr<IntersectionObserver::IntersectionObserver>> intersection_observers(heap());
+    intersection_observers.ensure_capacity(m_intersection_observers.size());
+    for (auto& observer : m_intersection_observers)
+        intersection_observers.append(observer);
+
+    for (auto& observer : intersection_observers) {
         // 1. Let rootBounds be observer’s root intersection rectangle.
         auto root_bounds = observer->root_intersection_rectangle();
 
diff --git a/Libraries/LibWeb/DOM/Document.h b/Libraries/LibWeb/DOM/Document.h
index 88a10bb5f59..74cd011e886 100644
--- a/Libraries/LibWeb/DOM/Document.h
+++ b/Libraries/LibWeb/DOM/Document.h
@@ -939,8 +939,8 @@ private:
 
     JS::GCPtr<CSS::VisualViewport> m_visual_viewport;
 
-    // NOTE: Not in the spec per say, but Document must be able to access all IntersectionObservers whose root is in the document.
-    OrderedHashTable<JS::NonnullGCPtr<IntersectionObserver::IntersectionObserver>> m_intersection_observers;
+    // NOTE: Not in the spec per se, but Document must be able to access all IntersectionObservers whose root is in the document.
+    IGNORE_GC OrderedHashTable<JS::NonnullGCPtr<IntersectionObserver::IntersectionObserver>> m_intersection_observers;
 
     // https://www.w3.org/TR/intersection-observer/#document-intersectionobservertaskqueued
     // Each document has an IntersectionObserverTaskQueued flag which is initialized to false.