--- a/editor/libeditor/HTMLEditRules.cpp
+++ b/editor/libeditor/HTMLEditRules.cpp
@@ -1450,17 +1450,20 @@ HTMLEditRules::WillLoadHTML(Selection* a
   NS_ENSURE_TRUE(aSelection && aCancel, NS_ERROR_NULL_POINTER);
 
   *aCancel = false;
 
   // Delete mBogusNode if it exists. If we really need one,
   // it will be added during post-processing in AfterEditInner().
 
   if (mBogusNode) {
-    mTextEditor->DeleteNode(mBogusNode);
+    if (NS_WARN_IF(!mHTMLEditor)) {
+      return NS_ERROR_UNEXPECTED;
+    }
+    mHTMLEditor->DeleteNode(mBogusNode);
     mBogusNode = nullptr;
   }
 
   return NS_OK;
 }
 
 nsresult
 HTMLEditRules::WillInsertBreak(Selection& aSelection,
@@ -3794,17 +3797,20 @@ HTMLEditRules::WillCSSIndent(Selection* 
     // Not a list item.
     else {
       if (curNode && IsBlockNode(*curNode)) {
         ChangeIndentation(*curNode->AsElement(), Change::plus);
         curQuote = nullptr;
       } else {
         if (!curQuote) {
           // First, check that our element can contain a div.
-          if (!mTextEditor->CanContainTag(*curParent, *nsGkAtoms::div)) {
+          if (NS_WARN_IF(!mHTMLEditor)) {
+            return NS_ERROR_UNEXPECTED;
+          }
+          if (!mHTMLEditor->CanContainTag(*curParent, *nsGkAtoms::div)) {
             return NS_OK; // cancelled
           }
 
           rv = SplitAsNeeded(*nsGkAtoms::div, curParent, offset);
           NS_ENSURE_SUCCESS(rv, rv);
           NS_ENSURE_STATE(mHTMLEditor);
           curQuote = mHTMLEditor->CreateNode(nsGkAtoms::div, curParent,
                                              offset);
@@ -4022,17 +4028,20 @@ HTMLEditRules::WillHTMLIndent(Selection*
         // One reason it might not go in prio blockquote is if we are now
         // in a different table cell.
         if (curQuote && InDifferentTableElements(curQuote, curNode)) {
           curQuote = nullptr;
         }
 
         if (!curQuote) {
           // First, check that our element can contain a blockquote.
-          if (!mTextEditor->CanContainTag(*curParent, *nsGkAtoms::blockquote)) {
+          if (NS_WARN_IF(!mHTMLEditor)) {
+            return NS_ERROR_UNEXPECTED;
+          }
+          if (!mHTMLEditor->CanContainTag(*curParent, *nsGkAtoms::blockquote)) {
             return NS_OK; // cancelled
           }
 
           rv = SplitAsNeeded(*nsGkAtoms::blockquote, curParent, offset);
           NS_ENSURE_SUCCESS(rv, rv);
           NS_ENSURE_STATE(mHTMLEditor);
           curQuote = mHTMLEditor->CreateNode(nsGkAtoms::blockquote, curParent,
                                              offset);
@@ -4766,17 +4775,17 @@ HTMLEditRules::WillAlign(Selection& aSel
       }
       // Clear out curDiv so that we don't put nodes after this one into it
     }
 
     // Need to make a div to put things in if we haven't already, or if this
     // node doesn't go in div we used earlier.
     if (!curDiv || transitionList[i]) {
       // First, check that our element can contain a div.
-      if (!mTextEditor->CanContainTag(*curParent, *nsGkAtoms::div)) {
+      if (!htmlEditor->CanContainTag(*curParent, *nsGkAtoms::div)) {
         // Cancelled
         return NS_OK;
       }
 
       rv = SplitAsNeeded(*nsGkAtoms::div, curParent, offset);
       NS_ENSURE_SUCCESS(rv, rv);
       curDiv = htmlEditor->CreateNode(nsGkAtoms::div, curParent, offset);
       NS_ENSURE_STATE(curDiv);
@@ -6385,17 +6394,20 @@ HTMLEditRules::ReturnInParagraph(Selecti
           TextEditUtils::HasMozAttr(GetAsDOMNode(sibling))) {
         NS_ENSURE_STATE(mHTMLEditor);
         newBRneeded = true;
         offset++;
       }
     } else {
       if (doesCRCreateNewP) {
         nsCOMPtr<nsIDOMNode> tmp;
-        rv = mTextEditor->SplitNode(aNode, aOffset, getter_AddRefs(tmp));
+        if (NS_WARN_IF(!mHTMLEditor)) {
+          return NS_ERROR_UNEXPECTED;
+        }
+        rv = mHTMLEditor->SplitNode(aNode, aOffset, getter_AddRefs(tmp));
         NS_ENSURE_SUCCESS(rv, rv);
         selNode = tmp;
       }
 
       newBRneeded = true;
       offset++;
     }
   } else {
@@ -6607,17 +6619,17 @@ HTMLEditRules::ReturnInListItem(Selectio
           nsCOMPtr<nsINode> list = aListItem.GetParentNode();
           int32_t itemOffset = list ? list->IndexOf(&aListItem) : -1;
 
           nsIAtom* listAtom = nodeAtom == nsGkAtoms::dt ? nsGkAtoms::dd
                                                         : nsGkAtoms::dt;
           nsCOMPtr<Element> newListItem =
             htmlEditor->CreateNode(listAtom, list, itemOffset + 1);
           NS_ENSURE_STATE(newListItem);
-          rv = mTextEditor->DeleteNode(&aListItem);
+          rv = htmlEditor->DeleteNode(&aListItem);
           NS_ENSURE_SUCCESS(rv, rv);
           rv = aSelection.Collapse(newListItem, 0);
           NS_ENSURE_SUCCESS(rv, rv);
 
           return NS_OK;
         }
 
         nsCOMPtr<Element> brNode;
@@ -8861,17 +8873,17 @@ HTMLEditRules::DocumentModifiedWorker()
   RefPtr<Selection> selection = htmlEditor->GetSelection();
   if (!selection) {
     return;
   }
 
   // Delete our bogus node, if we have one, since the document might not be
   // empty any more.
   if (mBogusNode) {
-    mTextEditor->DeleteNode(mBogusNode);
+    htmlEditor->DeleteNode(mBogusNode);
     mBogusNode = nullptr;
   }
 
   // Try to recreate the bogus node if needed.
   CreateBogusNodeIfNeeded(selection);
 }
 
 } // namespace mozilla

--- a/editor/libeditor/TextEditRules.h
+++ b/editor/libeditor/TextEditRules.h
@@ -219,18 +219,21 @@ protected:
   bool IsPasswordEditor() const;
   bool IsSingleLineEditor() const;
   bool IsPlaintextEditor() const;
   bool IsReadonly() const;
   bool IsDisabled() const;
   bool IsMailEditor() const;
   bool DontEchoPassword() const;
 
+private:
   // Note that we do not refcount the editor.
   TextEditor* mTextEditor;
+
+protected:
   // A buffer we use to store the real value of password editors.
   nsString mPasswordText;
   // A buffer we use to track the IME composition string.
   nsString mPasswordIMEText;
   uint32_t mPasswordIMEIndex;
   // Magic node acts as placeholder in empty doc.
   nsCOMPtr<nsIDOMNode> mBogusNode;
   // Cached selected node.