diff --git a/components/security_interstitials/core/browser/resources/interstitial_large.js b/components/security_interstitials/core/browser/resources/interstitial_large.js
index 066e8b6..0fa7dbf 100644
--- a/components/security_interstitials/core/browser/resources/interstitial_large.js
+++ b/components/security_interstitials/core/browser/resources/interstitial_large.js
@@ -13,7 +13,10 @@
  * @param {string} e The key that was just pressed.
  */
 function handleKeypress(e) {
-  var BYPASS_SEQUENCE = 'thisisnotsafe';
+  // HTTPS errors are serious and should not be ignored. For testing purposes,
+  // other approaches are both safer and have fewer side-effects.
+  // See https://goo.gl/ZcZixP for more details.
+  var BYPASS_SEQUENCE = window.atob('dGhpc2lzdW5zYWZl');
   if (BYPASS_SEQUENCE.charCodeAt(keyPressState) == e.keyCode) {
     keyPressState++;
     if (keyPressState == BYPASS_SEQUENCE.length) {