Merge branch 'redwood' into releaseRELBASE_20201024RC_20201024

1 files changed, 6 insertions, 0 deletions

diff --git a/dom/base/nsDocument.cpp b/dom/base/nsDocument.cpp
index 0b07ef4ec..144f048eb 100644
--- a/dom/base/nsDocument.cpp
+++ b/dom/base/nsDocument.cpp
@@ -3689,6 +3689,12 @@ nsDocument::DeleteShell()
   // objects for @font-face rules that came from the style set.
   RebuildUserFontSet();
 
+  if (mResizeObserverController) {
+    // If the shell is going away, we need to remove any links to this document
+    // from the observer.
+    mResizeObserverController->DetachFromDocument();
+  }
+
   nsIPresShell* oldShell = mPresShell;
   mPresShell = nullptr;
   UpdateFrameRequestCallbackSchedulingState(oldShell);