diff --git a/browser/root-certs b/browser/root-certs
index f76bc74..6c57965 100755
--- a/browser/root-certs
+++ b/browser/root-certs
@@ -34,8 +34,6 @@ function getRootCerts(callback) {
           + '"' + key + '":\n';
     });
     body += ''
-      + '\n'
-      + 'certs.__proto__ = null;\n'
       + '\n'
       + '// Use hash table for efficiency:\n'
       + 'var trusted = Object.keys(certs).reduce(function(trusted, key) {\n'
@@ -45,20 +43,20 @@ function getRootCerts(callback) {
       + '  pem = pem.replace(/\\s+/g, "");\n'
       + '  trusted[pem] = key;\n'
       + '  return trusted;\n'
-      + '}, { __proto__: null });\n'
+      + '}, {});\n'
       + '\n'
       + 'function getTrusted(pem) {\n'
       + '  pem = pem + "";\n'
       + '  pem = pem.replace(/-----BEGIN CERTIFICATE-----/g, "");\n'
       + '  pem = pem.replace(/-----END CERTIFICATE-----/g, "");\n'
       + '  pem = pem.replace(/\\s+/g, "");\n'
-      + '  if (pem === "__proto__") return;\n'
+      + '  if (!Object.prototype.hasOwnProperty.call(certs, pem)) return;\n'
       + '  return certs[pem];\n'
       + '}\n'
       + '\n'
       + 'function getCert(name) {\n'
       + '  name = name.replace(/^\s+|\s+$/g, "");\n'
-      + '  if (name === "__proto__") return;\n'
+      + '  if (!Object.prototype.hasOwnProperty.call(trusted, name)) return;\n'
       + '  return trusted[name];\n'
       + '}\n'
       + '\n'
diff --git a/lib/common/RootCerts.js b/lib/common/RootCerts.js
index f4efa35..5c5629e 100644
--- a/lib/common/RootCerts.js
+++ b/lib/common/RootCerts.js
@@ -3704,8 +3704,6 @@ var certs = {
 + "-----END CERTIFICATE-----\n"
 };
 
-certs.__proto__ = null;
-
 // Use hash table for efficiency:
 var trusted = Object.keys(certs).reduce(function(trusted, key) {
   var pem = certs[key];
@@ -3714,20 +3712,20 @@ var trusted = Object.keys(certs).reduce(function(trusted, key) {
   pem = pem.replace(/\s+/g, "");
   trusted[pem] = key;
   return trusted;
-}, { __proto__: null });
+}, {});
 
 function getTrusted(pem) {
   pem = pem + "";
   pem = pem.replace(/-----BEGIN CERTIFICATE-----/g, "");
   pem = pem.replace(/-----END CERTIFICATE-----/g, "");
   pem = pem.replace(/\s+/g, "");
-  if (pem === "__proto__") return;
+  if (!Object.prototype.hasOwnProperty.call(certs, pem)) return;
   return certs[pem];
 }
 
 function getCert(name) {
   name = name.replace(/^s+|s+$/g, "");
-  if (name === "__proto__") return;
+  if (!Object.prototype.hasOwnProperty.call(trusted, name)) return;
   return trusted[name];
 }