From 096dffbcab9691b9af2f2fd29efd046b105db8c8 Mon Sep 17 00:00:00 2001
From: Olli Pettay <Olli.Pettay@helsinki.fi>
Date: Sat, 25 Apr 2026 11:03:41 +0200
Subject: [PATCH] Bug 2025370 - Properly handle error case in
 EventListenerManager::GetTypedEventHandler

---
 dom/events/EventListenerManager.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/dom/events/EventListenerManager.cpp b/dom/events/EventListenerManager.cpp
index 7db30be4e0..a5bf65cea9 100644
--- a/dom/events/EventListenerManager.cpp
+++ b/dom/events/EventListenerManager.cpp
@@ -1632,8 +1632,12 @@ EventListenerManager::GetTypedEventHandler(nsIAtom* aEventName,
 
   JSEventHandler* jsEventHandler = listener->GetJSEventHandler();
 
+  Maybe<RefPtr<JSEventHandler>> pin;
   if (listener->mHandlerIsString) {
-    CompileEventHandlerInternal(listener, nullptr, nullptr);
+    pin.emplace(jsEventHandler);
+    if (NS_FAILED(CompileEventHandlerInternal(listener, nullptr, nullptr))) {
+      listener = nullptr;
+    }
   }
 
   const TypedEventHandler& typedHandler =