--- a/editor/libeditor/HTMLStyleEditor.cpp
+++ b/editor/libeditor/HTMLStyleEditor.cpp
@@ -130,20 +130,18 @@ HTMLEditor::SetInlineProperty(nsIAtom* a
 
   bool cancel, handled;
   TextRulesInfo ruleInfo(EditAction::setTextProperty);
   // Protect the edit rules object from dying
   nsresult rv = rules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
   NS_ENSURE_SUCCESS(rv, rv);
   if (!cancel && !handled) {
     // Loop through the ranges in the selection
-    uint32_t rangeCount = selection->RangeCount();
-    for (uint32_t rangeIdx = 0; rangeIdx < rangeCount; rangeIdx++) {
-      RefPtr<nsRange> range = selection->GetRangeAt(rangeIdx);
-
+    AutoRangeArray arrayOfRanges(selection);
+    for (auto& range : arrayOfRanges.mRanges) {
       // Adjust range to include any ancestors whose children are entirely
       // selected
       rv = PromoteInlineRange(*range);
       NS_ENSURE_SUCCESS(rv, rv);
 
       // Check for easy case: both range endpoints in same text node
       nsCOMPtr<nsINode> startNode = range->GetStartParent();
       nsCOMPtr<nsINode> endNode = range->GetEndParent();
@@ -1235,35 +1233,31 @@ HTMLEditor::RemoveInlinePropertyImpl(nsI
   bool cancel, handled;
   TextRulesInfo ruleInfo(EditAction::removeTextProperty);
   // Protect the edit rules object from dying
   nsCOMPtr<nsIEditRules> rules(mRules);
   nsresult rv = rules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
   NS_ENSURE_SUCCESS(rv, rv);
   if (!cancel && !handled) {
     // Loop through the ranges in the selection
-    uint32_t rangeCount = selection->RangeCount();
     // Since ranges might be modified by SplitStyleAboveRange, we need hold
     // current ranges
-    AutoTArray<OwningNonNull<nsRange>, 8> arrayOfRanges;
-    for (uint32_t rangeIdx = 0; rangeIdx < rangeCount; ++rangeIdx) {
-      arrayOfRanges.AppendElement(*selection->GetRangeAt(rangeIdx));
-    }
-    for (auto& range : arrayOfRanges) {
+    AutoRangeArray arrayOfRanges(selection);
+    for (auto& range : arrayOfRanges.mRanges) {
       if (aProperty == nsGkAtoms::name) {
         // Promote range if it starts or end in a named anchor and we want to
         // remove named anchors
-        rv = PromoteRangeIfStartsOrEndsInNamedAnchor(range);
+        rv = PromoteRangeIfStartsOrEndsInNamedAnchor(*range);
         if (NS_WARN_IF(NS_FAILED(rv))) {
           return rv;
         }
       } else {
         // Adjust range to include any ancestors whose children are entirely
         // selected
-        rv = PromoteInlineRange(range);
+        rv = PromoteInlineRange(*range);
         if (NS_WARN_IF(NS_FAILED(rv))) {
           return rv;
         }
       }
 
       // Remove this style from ancestors of our range endpoints, splitting
       // them as appropriate
       rv = SplitStyleAboveRange(range, aProperty, aAttribute);
@@ -1389,20 +1383,18 @@ HTMLEditor::RelativeFontChange(FontSize 
   // Wrap with txn batching, rules sniffing, and selection preservation code
   AutoEditBatch batchIt(this);
   AutoRules beginRulesSniffing(this, EditAction::setTextProperty,
                                nsIEditor::eNext);
   AutoSelectionRestorer selectionRestorer(selection, this);
   AutoTransactionsConserveSelection dontSpazMySelection(this);
 
   // Loop through the ranges in the selection
-  uint32_t rangeCount = selection->RangeCount();
-  for (uint32_t rangeIdx = 0; rangeIdx < rangeCount; ++rangeIdx) {
-    RefPtr<nsRange> range = selection->GetRangeAt(rangeIdx);
-
+  AutoRangeArray arrayOfRanges(selection);
+  for (auto& range : arrayOfRanges.mRanges) {
     // Adjust range to include any ancestors with entirely selected children
     nsresult rv = PromoteInlineRange(*range);
     NS_ENSURE_SUCCESS(rv, rv);
 
     // Check for easy case: both range endpoints in same text node
     nsCOMPtr<nsINode> startNode = range->GetStartParent();
     nsCOMPtr<nsINode> endNode = range->GetEndParent();
     if (startNode == endNode && IsTextNode(startNode)) {