diff --git a/Libraries/LibGC/Heap.cpp b/Libraries/LibGC/Heap.cpp
index 99b5643e03e..3c907b608cb 100644
--- a/Libraries/LibGC/Heap.cpp
+++ b/Libraries/LibGC/Heap.cpp
@@ -240,23 +240,35 @@ AK::JsonObject Heap::dump_graph()
 void Heap::collect_garbage(CollectionType collection_type, bool print_report)
 {
     VERIFY(!m_collecting_garbage);
-    TemporaryChange change(m_collecting_garbage, true);
 
-    Core::ElapsedTimer collection_measurement_timer;
-    if (print_report)
-        collection_measurement_timer.start();
+    {
+        TemporaryChange change(m_collecting_garbage, true);
 
-    if (collection_type == CollectionType::CollectGarbage) {
-        if (m_gc_deferrals) {
-            m_should_gc_when_deferral_ends = true;
-            return;
+        Core::ElapsedTimer collection_measurement_timer;
+        if (print_report)
+            collection_measurement_timer.start();
+
+        if (collection_type == CollectionType::CollectGarbage) {
+            if (m_gc_deferrals) {
+                m_should_gc_when_deferral_ends = true;
+                return;
+            }
+            HashMap<Cell*, HeapRoot> roots;
+            gather_roots(roots);
+            mark_live_cells(roots);
         }
-        HashMap<Cell*, HeapRoot> roots;
-        gather_roots(roots);
-        mark_live_cells(roots);
+        finalize_unmarked_cells();
+        sweep_dead_cells(print_report, collection_measurement_timer);
     }
-    finalize_unmarked_cells();
-    sweep_dead_cells(print_report, collection_measurement_timer);
+
+    auto tasks = move(m_post_gc_tasks);
+    for (auto& task : tasks)
+        task();
+}
+
+void Heap::enqueue_post_gc_task(AK::Function<void()> task)
+{
+    m_post_gc_tasks.append(move(task));
 }
 
 void Heap::gather_roots(HashMap<Cell*, HeapRoot>& roots)
diff --git a/Libraries/LibGC/Heap.h b/Libraries/LibGC/Heap.h
index e9275ca5507..5b39c1b6f80 100644
--- a/Libraries/LibGC/Heap.h
+++ b/Libraries/LibGC/Heap.h
@@ -76,6 +76,8 @@ public:
 
     bool is_gc_deferred() const { return m_gc_deferrals > 0; }
 
+    void enqueue_post_gc_task(AK::Function<void()>);
+
 private:
     friend class MarkingVisitor;
     friend class GraphConstructorVisitor;
@@ -151,6 +153,8 @@ private:
     bool m_collecting_garbage { false };
     StackInfo m_stack_info;
     AK::Function<void(HashMap<Cell*, GC::HeapRoot>&)> m_gather_embedder_roots;
+
+    Vector<AK::Function<void()>> m_post_gc_tasks;
 } SWIFT_IMMORTAL_REFERENCE;
 
 inline void Heap::did_create_root(Badge<RootImpl>, RootImpl& impl)
diff --git a/Libraries/LibJS/Runtime/FinalizationRegistry.cpp b/Libraries/LibJS/Runtime/FinalizationRegistry.cpp
index 47e03a64607..2f03549141f 100644
--- a/Libraries/LibJS/Runtime/FinalizationRegistry.cpp
+++ b/Libraries/LibJS/Runtime/FinalizationRegistry.cpp
@@ -57,8 +57,13 @@ void FinalizationRegistry::remove_dead_cells(Badge<GC::Heap>)
         any_cells_were_removed = true;
         break;
     }
-    if (any_cells_were_removed)
-        vm().host_enqueue_finalization_registry_cleanup_job(*this);
+    if (any_cells_were_removed) {
+        // NOTE: We make a GC::Root here to ensure that the FinalizationRegistry stays alive
+        //       even if a subsequent GC is triggered before the callback has a chance to run.
+        heap().enqueue_post_gc_task([that = GC::make_root(this)]() {
+            that->vm().host_enqueue_finalization_registry_cleanup_job(*that);
+        });
+    }
 }
 
 // 9.13 CleanupFinalizationRegistry ( finalizationRegistry ), https://tc39.es/ecma262/#sec-cleanup-finalization-registry
diff --git a/Tests/LibWeb/Crash/JS/finalization-registry-basic.html b/Tests/LibWeb/Crash/JS/finalization-registry-basic.html
new file mode 100644
index 00000000000..5287da46dc6
--- /dev/null
+++ b/Tests/LibWeb/Crash/JS/finalization-registry-basic.html
@@ -0,0 +1,19 @@
+<script src="../include.js"></script>
+<script>
+
+// NOTE: This test is only reliable when GC'ing after each allocation.
+
+const registry = new FinalizationRegistry((heldValue) => {
+    console.log(heldValue);
+});
+
+const makeGarbage = () => {
+    registry.register(new String("ok"), "hello");
+};
+makeGarbage();
+
+if (window.internals !== undefined)
+    internals.gc();
+
+println("PASS");
+</script>