--- a/security/manager/ssl/src/nsNSSComponent.cpp
+++ b/security/manager/ssl/src/nsNSSComponent.cpp
@@ -698,16 +698,25 @@ static const CipherPref sCipherPrefs[] =
 
 static const int32_t OCSP_ENABLED_DEFAULT = 1;
 static const bool REQUIRE_SAFE_NEGOTIATION_DEFAULT = false;
 static const bool ALLOW_UNRESTRICTED_RENEGO_DEFAULT = false;
 static const bool FALSE_START_ENABLED_DEFAULT = true;
 static const bool NPN_ENABLED_DEFAULT = true;
 static const bool ALPN_ENABLED_DEFAULT = false;
 
+static void
+ConfigureTLSSessionIdentifiers()
+{
+  bool disableSessionIdentifiers =
+    Preferences::GetBool("security.ssl.disable_session_identifiers", false);
+  SSL_OptionSetDefault(SSL_ENABLE_SESSION_TICKETS, !disableSessionIdentifiers);
+  SSL_OptionSetDefault(SSL_NO_CACHE, disableSessionIdentifiers);
+}
+
 namespace {
 
 class CipherSuiteChangeObserver : public nsIObserver
 {
 public:
   NS_DECL_ISUPPORTS
   NS_DECL_NSIOBSERVER
 
@@ -989,17 +998,17 @@ nsNSSComponent::InitializeNSS()
     return NS_ERROR_UNEXPECTED;
   }
 
   DisableMD5();
   // Initialize the certverifier log before calling any functions that library.
   InitCertVerifierLog();
   LoadLoadableRoots();
 
-  SSL_OptionSetDefault(SSL_ENABLE_SESSION_TICKETS, true);
+  ConfigureTLSSessionIdentifiers();
 
   bool requireSafeNegotiation =
     Preferences::GetBool("security.ssl.require_safe_negotiation",
                          REQUIRE_SAFE_NEGOTIATION_DEFAULT);
   SSL_OptionSetDefault(SSL_REQUIRE_SAFE_NEGOTIATION, requireSafeNegotiation);
 
   bool allowUnrestrictedRenego =
     Preferences::GetBool("security.ssl.allow_unrestricted_renego_everywhere__temporarily_available_pref",
@@ -1299,16 +1308,18 @@ nsNSSComponent::Observe(nsISupports* aSu
     } else if (prefName.EqualsLiteral("security.ssl.enable_npn")) {
       SSL_OptionSetDefault(SSL_ENABLE_NPN,
                            Preferences::GetBool("security.ssl.enable_npn",
                                                 NPN_ENABLED_DEFAULT));
     } else if (prefName.EqualsLiteral("security.ssl.enable_alpn")) {
       SSL_OptionSetDefault(SSL_ENABLE_ALPN,
                            Preferences::GetBool("security.ssl.enable_alpn",
                                                 ALPN_ENABLED_DEFAULT));
+    } else if (prefName.Equals("security.ssl.disable_session_identifiers")) {
+      ConfigureTLSSessionIdentifiers();
     } else if (prefName.EqualsLiteral("security.OCSP.enabled") ||
                prefName.EqualsLiteral("security.OCSP.require") ||
                prefName.EqualsLiteral("security.OCSP.GET.enabled") ||
                prefName.EqualsLiteral("security.ssl.enable_ocsp_stapling") ||
                prefName.EqualsLiteral("security.cert_pinning.enforcement_level")) {
       MutexAutoLock lock(mutex);
       setValidationOptions(false, lock);
     } else if (prefName.EqualsLiteral("network.ntlm.send-lm-response")) {