diff --git a/src/lib/style-transformer.html b/src/lib/style-transformer.html
index 94775b5589..60503fe75e 100644
--- a/src/lib/style-transformer.html
+++ b/src/lib/style-transformer.html
@@ -109,11 +109,7 @@
           cb = function(rule) {
             rule.selector = self._slottedToContent(rule.selector);
             rule.selector = rule.selector.replace(ROOT, ':host > *');
-            rule.selector = rule.selector.split(',').map(function(s) {
-              s = s.replace(HOST_DIR, HOST_DIR_REPLACE);
-              s = s.replace(DIR_PAREN, SHADOW_DIR_REPLACE);
-              return s;
-            }).join(',');
+            rule.selector = self._dirShadowTransform(rule.selector);
             if (callback) {
               callback(rule);
             }
@@ -320,6 +316,14 @@
         return cssText.replace(SLOTTED_PAREN, CONTENT + '> $1');
       },
 
+      _dirShadowTransform: function(selector) {
+        return selector.split(',').map(function(s) {
+          s = s.replace(HOST_DIR, HOST_DIR_REPLACE);
+          s = s.replace(DIR_PAREN, SHADOW_DIR_REPLACE);
+          return s;
+        }).join(',');
+      },
+
       SCOPE_NAME: 'style-scope'
     };
 
diff --git a/test/runner.html b/test/runner.html
index a5a6803e73..d18d6ba6ca 100644
--- a/test/runner.html
+++ b/test/runner.html
@@ -105,7 +105,7 @@
       'unit/custom-style-transformed.html?lazyRegister=true&useNativeCSSProperties=true&dom=shadow'
     ];
 
-    if (window.customElements || document.registerElement) {
+    if ('import' in document.createElement('link') && (window.customElements || document.registerElement)) {
       suites.push('unit/attach-detach-timing.html');
     }
     if (/edge/i.test(navigator.userAgent)) {