From 2249fbdf495bb0f018445df0db1dcf0d06f6a1d5 Mon Sep 17 00:00:00 2001
From: Moonchild <moonchild@palemoon.org>
Date: Fri, 10 Mar 2023 11:44:28 +0100
Subject: [PATCH] Issue #2135 - Follow-up: Check for aElement not being null

This was introduced to Make <link rel="stylesheet"> work in shadow trees.
eElement can, however, be `null` here and if so, it would crash.
---
 layout/style/Loader.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/layout/style/Loader.cpp b/layout/style/Loader.cpp
index 3d1e4826d5..48ca1739dc 100644
--- a/layout/style/Loader.cpp
+++ b/layout/style/Loader.cpp
@@ -2118,7 +2118,7 @@ Loader::LoadStyleLink(nsIContent* aElement,
 
   PrepareSheet(sheet, aTitle, aMedia, nullptr, nullptr, *aIsAlternate, *aIsExplicitlyEnabled);
 
-  if (aElement->HasFlag(NODE_IS_IN_SHADOW_TREE)) {
+  if (aElement && aElement->HasFlag(NODE_IS_IN_SHADOW_TREE)) {
     aElement->GetContainingShadow()->InsertSheet(sheet, aElement);
   } else {
     rv = InsertSheetInDoc(sheet, aElement, mDocument);