diff --git a/netwerk/base/security-prefs.js b/netwerk/base/security-prefs.js
index 5351d7c04d..cfbbf4a457 100644
--- a/netwerk/base/security-prefs.js
+++ b/netwerk/base/security-prefs.js
@@ -3,7 +3,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 pref("security.tls.version.min", 1);
-pref("security.tls.version.max", 3);
+pref("security.tls.version.max", 4);
 pref("security.tls.version.fallback-limit", 3);
 pref("security.tls.insecure_fallback_hosts", "");
 pref("security.tls.unrestricted_rc4_fallback", false);