--- a/layout/base/ServoRestyleManager.cpp
+++ b/layout/base/ServoRestyleManager.cpp
@@ -826,17 +826,16 @@ ServoRestyleManager::ProcessPostTraversa
     if (MOZ_UNLIKELY(displayContentsStyle)) {
       MOZ_ASSERT(!styleFrame);
       PresContext()->FrameConstructor()->
         ChangeRegisteredDisplayContentsStyleFor(aElement, upToDateContext);
     }
 
     if (styleFrame) {
       UpdateAdditionalStyleContexts(styleFrame, aRestyleState);
-      styleFrame->UpdateStyleOfOwnedAnonBoxes(childrenRestyleState);
     }
 
     if (!aElement->GetParent()) {
       // This is the root.  Update styles on the viewport as needed.
       ViewportFrame* viewport =
         do_QueryFrame(mPresContext->PresShell()->GetRootFrame());
       if (viewport) {
         // NB: The root restyle state, not the one for our children!
@@ -886,20 +885,21 @@ ServoRestyleManager::ProcessPostTraversa
     }
   }
 
   // We want to update frame pseudo-element styles after we've traversed our
   // kids, because some of those updates (::first-line/::first-letter) need to
   // modify the styles of the kids, and the child traversal above would just
   // clobber those modifications.
   if (styleFrame) {
-    // Process anon box wrapper frames before ::first-line bits.
+    // Process anon boxes and other pseudos before ::first-line bits.
     childrenRestyleState.ProcessWrapperRestyles(styleFrame);
 
     if (wasRestyled) {
+      styleFrame->UpdateStyleOfOwnedAnonBoxes(childrenRestyleState);
       styleFrame->UpdatePseudoElementStylesIfNeeded(childrenRestyleState);
     } else if (traverseElementChildren &&
                styleFrame->IsFrameOfType(nsIFrame::eBlockFrame)) {
       // Even if we were not restyled, if we're a block with a first-line and
       // one of our descendant elements which is on the first line was restyled,
       // we need to update the styles of things on the first line, because
       // they're wrong now.
       //