--- a/dom/base/Element.cpp
+++ b/dom/base/Element.cpp
@@ -4372,17 +4372,17 @@ NoteDirtyElement(Element* aElement, uint
   // If there's no existing restyle root, or if the root is already aElement,
   // just note the root+bits and return.
   if (!existingRoot || existingRoot == aElement) {
     doc->SetServoRestyleRoot(aElement, existingBits | aBit);
     return;
   }
 
   // There is an existing restyle root - walk up the tree from our element,
-  // propagating bits as wel go.
+  // propagating bits as we go.
   const bool reachedDocRoot = !parent || !PropagateBits(parent, aBit, existingRoot);
 
   if (!reachedDocRoot || existingRoot == doc) {
       // We're a descendant of the existing root. All that's left to do is to
       // make sure the bit we propagated is also registered on the root.
       doc->SetServoRestyleRoot(existingRoot, existingBits | aBit);
   } else {
     // We reached the root without crossing the pre-existing restyle root. We