--- a/editor/libeditor/HTMLEditRules.cpp
+++ b/editor/libeditor/HTMLEditRules.cpp
@@ -5867,20 +5867,25 @@ HTMLEditRules::WillAlign(const nsAString
       if (useCSS) {
         HTMLEditorRef().mCSSEditUtils->SetCSSEquivalentToHTMLStyle(
                                          curNode->AsElement(), nullptr,
                                          nsGkAtoms::align, &aAlignType, false);
         curDiv = nullptr;
         continue;
       }
       if (HTMLEditUtils::IsList(atCurNode.GetContainer())) {
-        // If we don't use CSS, add a contraint to list element: they have to
-        // be inside another list, i.e., >= second level of nesting
+        // If we don't use CSS, add a content to list element: they have to
+        // be inside another list, i.e., >= second level of nesting.
+        // XXX AlignInnerBlocks() handles list item elements and table cells.
+        //     Is it intentional to change alignment of nested other type
+        //     descendants too?
         rv = AlignInnerBlocks(*curNode, aAlignType);
-        NS_ENSURE_SUCCESS(rv, rv);
+        if (NS_WARN_IF(NS_FAILED(rv))) {
+          return rv;
+        }
         curDiv = nullptr;
         continue;
       }
       // 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.
@@ -5919,20 +5924,16 @@ HTMLEditRules::WillAlign(const nsAString
     if (NS_WARN_IF(NS_FAILED(rv))) {
       return rv;
     }
   }
 
   return NS_OK;
 }
 
-
-/**
- * AlignInnerBlocks() aligns inside table cells or list items.
- */
 nsresult
 HTMLEditRules::AlignInnerBlocks(nsINode& aNode,
                                 const nsAString& aAlignType)
 {
   MOZ_ASSERT(IsEditorDataAvailable());
 
   // Gather list of table cells or list items
   nsTArray<OwningNonNull<nsINode>> nodeArray;

--- a/editor/libeditor/HTMLEditRules.h
+++ b/editor/libeditor/HTMLEditRules.h
@@ -396,17 +396,26 @@ protected:
    * Called if nobody handles the edit action to make an element absolute
    * positioned.
    * This method actually changes the element which is computed by
    * WillAbsolutePosition() to absolute positioned.
    * Therefore, this might cause destroying the HTML editor.
    */
   MOZ_MUST_USE nsresult DidAbsolutePosition();
 
-  nsresult AlignInnerBlocks(nsINode& aNode, const nsAString& aAlignType);
+  /**
+   * AlignInnerBlocks() calls AlignBlockContents() for every list item element
+   * and table cell element in aNode.
+   *
+   * @param aNode               The node whose descendants should be aligned
+   *                            to aAlignType.
+   * @param aAlignType          New value of align attribute of <div>.
+   */
+  MOZ_MUST_USE nsresult
+  AlignInnerBlocks(nsINode& aNode, const nsAString& aAlignType);
 
   /**
    * AlignBlockContents() sets align attribute of <div> element which is
    * only child of aNode to aAlignType.  If aNode has 2 or more children or
    * does not have a <div> element has only child, inserts a <div> element
    * into aNode and move all children of aNode into the new <div> element.
    *
    * @param aNode               The node whose contents should be aligned