--- a/editor/libeditor/EditorUtils.h
+++ b/editor/libeditor/EditorUtils.h
@@ -2,16 +2,17 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 
 #ifndef mozilla_EditorUtils_h
 #define mozilla_EditorUtils_h
 
+#include "mozilla/dom/Selection.h"
 #include "mozilla/EditorBase.h"
 #include "mozilla/GuardObjects.h"
 #include "nsCOMPtr.h"
 #include "nsDebug.h"
 #include "nsIDOMNode.h"
 #include "nsIEditor.h"
 #include "nscore.h"
 
@@ -21,20 +22,16 @@ class nsIDOMDocument;
 class nsIDOMEvent;
 class nsISimpleEnumerator;
 class nsITransferable;
 class nsRange;
 
 namespace mozilla {
 template <class T> class OwningNonNull;
 
-namespace dom {
-class Selection;
-} // namespace dom
-
 /***************************************************************************
  * EditActionResult is useful to return multiple results of an editor
  * action handler without out params.
  * Note that when you return an anonymous instance from a method, you should
  * use EditActionIgnored(), EditActionHandled() or EditActionCanceled() for
  * easier to read.  In other words, EditActionResult should be used when
  * declaring return type of a method, being an argument or defined as a local
  * variable.
@@ -317,16 +314,33 @@ public:
     }
   }
 
 protected:
   EditorBase* mEditorBase;
   MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 
+class MOZ_STACK_CLASS AutoRangeArray final
+{
+public:
+  AutoRangeArray(dom::Selection* aSelection)
+  {
+    if (!aSelection) {
+      return;
+    }
+    uint32_t rangeCount = aSelection->RangeCount();
+    for (uint32_t i = 0; i < rangeCount; i++) {
+      mRanges.AppendElement(*aSelection->GetRangeAt(i));
+    }
+  }
+
+  AutoTArray<mozilla::OwningNonNull<nsRange>, 8> mRanges;
+};
+
 /******************************************************************************
  * some helper classes for iterating the dom tree
  *****************************************************************************/
 
 class BoolDomIterFunctor
 {
 public:
   virtual bool operator()(nsINode* aNode) const = 0;

--- a/editor/libeditor/HTMLEditRules.cpp
+++ b/editor/libeditor/HTMLEditRules.cpp
@@ -2447,20 +2447,18 @@ HTMLEditRules::WillDeleteSelection(Selec
           NS_ENSURE_SUCCESS(rv, rv);
           return NS_OK;
         }
 
         // Else blocks not same type, or not siblings.  Delete everything
         // except table elements.
         join = true;
 
-        uint32_t rangeCount = aSelection->RangeCount();
-        for (uint32_t rangeIdx = 0; rangeIdx < rangeCount; ++rangeIdx) {
-          OwningNonNull<nsRange> range = *aSelection->GetRangeAt(rangeIdx);
-
+        AutoRangeArray arrayOfRanges(aSelection);
+        for (auto& range : arrayOfRanges.mRanges) {
           // Build a list of nodes in the range
           nsTArray<OwningNonNull<nsINode>> arrayOfNodes;
           TrivialFunctor functor;
           DOMSubtreeIterator iter;
           nsresult rv = iter.Init(*range);
           NS_ENSURE_SUCCESS(rv, rv);
           iter.AppendList(functor, arrayOfNodes);