diff -u b/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php b/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php
--- b/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php
@@ -63,8 +63,9 @@
       //@todo Remove when https://github.com/jcalderonzumba/gastonjs/issues/19
       // is fixed. Currently clicking anchors/buttons with nested elements is
       // not possible, which is why we use Javascript's native click method.
-      $css_selector = addcslashes($css_selector, "'");
-      $this->getSession()->executeScript("document.querySelectorAll('" . $css_selector . "')[0].click()");
+      $xpath = $this->cssSelectToXpath($css_selector);
+      $xpath = addcslashes($xpath, "'");
+      $this->getSession()->executeScript("document.evaluate('" . $xpath . "', document, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue.click()");
     }
   }