1 files changed, 5 insertions, 0 deletions
diff --git a/layout/reftests/webcomponents/cross-tree-selection-1.html b/layout/reftests/webcomponents/cross-tree-selection-1.html
index 1e4f02747..01e7317f2 100644
--- a/layout/reftests/webcomponents/cross-tree-selection-1.html
+++ b/layout/reftests/webcomponents/cross-tree-selection-1.html
@@ -3,6 +3,11 @@
 <head>
   <script>
     function tweak() {
+      if (!document.body.createShadowRoot) {
+        document.documentElement.className = "";
+        return;
+      }
+
       var host = document.getElementById("host");
       var shadow = host.createShadowRoot();