2 files changed, 7 insertions, 1 deletions
diff --git a/src/ui/host/RoutedEventDispatch.h b/src/ui/host/RoutedEventDispatch.h
index ae1421ee..2ab51645 100644
--- a/src/ui/host/RoutedEventDispatch.h
+++ b/src/ui/host/RoutedEventDispatch.h
@@ -25,6 +25,8 @@ void DispatchEvent(
     controls::Control* const original_sender,
     events::RoutedEvent<EventArgs>* (controls::Control::*event_ptr)(),
     controls::Control* const last_receiver, Args&&... args) {
+  if (original_sender == nullptr) return;
+
   CRU_UNUSED(event_name)
 
   if (original_sender == last_receiver) {
@@ -41,7 +43,9 @@ void DispatchEvent(
   auto parent = original_sender;
   while (parent != last_receiver) {
     receive_list.push_back(parent);
-    parent = parent->GetParent();
+    auto p = parent->GetParent();
+    assert(!(p == nullptr && last_receiver != nullptr));
+    parent = p;
   }
 
   if constexpr (debug_flags::routed_event) {
diff --git a/src/ui/host/WindowHost.cpp b/src/ui/host/WindowHost.cpp
index 6849d000..91b5f438 100644
--- a/src/ui/host/WindowHost.cpp
+++ b/src/ui/host/WindowHost.cpp
@@ -53,6 +53,8 @@ bool IsAncestor(controls::Control* control, controls::Control* ancestor) {
 
 // Ancestor at last.
 std::vector<controls::Control*> GetAncestorList(controls::Control* control) {
+  if (control == nullptr) return {};
+
   std::vector<controls::Control*> l;
   while (control != nullptr) {
     l.push_back(control);