From 15dfc05d00dca9d8c67617abb3c1df53e29852ed Mon Sep 17 00:00:00 2001
From: Emily McDonough <emcdonough@mozilla.com>
Date: Tue, 9 Aug 2022 22:23:17 +0000
Subject: [PATCH] Bug 1783783 - Add null-check for aParentFrame when computing
 used page values in nsCSSFrameConstructor r=dholbert

Differential Revision: https://phabricator.services.mozilla.com/D154135
---
 layout/base/nsCSSFrameConstructor.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/layout/base/nsCSSFrameConstructor.cpp b/layout/base/nsCSSFrameConstructor.cpp
index 1b2a2aa1a0f2..5f52dc09e917 100644
--- a/layout/base/nsCSSFrameConstructor.cpp
+++ b/layout/base/nsCSSFrameConstructor.cpp
@@ -5491,7 +5491,7 @@ void nsCSSFrameConstructor::AddFrameConstructionItemsInternal(
   bool pageNameBreak = false;
   // TODO: We should document why the TextIsOnlyWhitespace() check is needed.
   // This will be documented as part of fixing Bug 1782324
-  if (aState.mPresContext->IsPaginated() &&
+  if (aParentFrame && aState.mPresContext->IsPaginated() &&
       StaticPrefs::layout_css_named_pages_enabled() &&
       !aContent->TextIsOnlyWhitespace()) {
     // TODO: This is slightly incorrect! See Bug 1764437
-- 
2.11.4.GIT