--- a/dom/base/nsContentUtils.cpp
+++ b/dom/base/nsContentUtils.cpp
@@ -285,16 +285,17 @@ nsString* nsContentUtils::sModifierSepar
 bool nsContentUtils::sInitialized = false;
 bool nsContentUtils::sIsFullScreenApiEnabled = false;
 bool nsContentUtils::sIsUnprefixedFullscreenApiEnabled = false;
 bool nsContentUtils::sTrustedFullScreenOnly = true;
 bool nsContentUtils::sIsCutCopyAllowed = true;
 bool nsContentUtils::sIsFrameTimingPrefEnabled = false;
 bool nsContentUtils::sIsPerformanceTimingEnabled = false;
 bool nsContentUtils::sIsResourceTimingEnabled = false;
+bool nsContentUtils::sIsPerformanceNavigationTimingEnabled = false;
 bool nsContentUtils::sIsUserTimingLoggingEnabled = false;
 bool nsContentUtils::sIsFormAutofillAutocompleteEnabled = false;
 bool nsContentUtils::sIsWebComponentsEnabled = false;
 bool nsContentUtils::sIsCustomElementsEnabled = false;
 bool nsContentUtils::sDevToolsEnabled = false;
 bool nsContentUtils::sSendPerformanceTimingNotifications = false;
 bool nsContentUtils::sUseActivityCursor = false;
 bool nsContentUtils::sAnimationsAPICoreEnabled = false;
@@ -686,16 +687,19 @@ nsContentUtils::Init()
                                "dom.allow_cut_copy", true);
 
   Preferences::AddBoolVarCache(&sIsPerformanceTimingEnabled,
                                "dom.enable_performance", true);
 
   Preferences::AddBoolVarCache(&sIsResourceTimingEnabled,
                                "dom.enable_resource_timing", true);
 
+  Preferences::AddBoolVarCache(&sIsPerformanceNavigationTimingEnabled,
+                               "dom.enable_performance_navigation_timing", true);
+
   Preferences::AddBoolVarCache(&sIsUserTimingLoggingEnabled,
                                "dom.performance.enable_user_timing_logging", false);
 
   Preferences::AddBoolVarCache(&sIsFrameTimingPrefEnabled,
                                "dom.enable_frame_timing", false);
 
   Preferences::AddBoolVarCache(&sIsFormAutofillAutocompleteEnabled,
                                "dom.forms.autocomplete.formautofill", false);

--- a/dom/base/nsContentUtils.h
+++ b/dom/base/nsContentUtils.h
@@ -2269,16 +2269,24 @@ public:
    * Returns true if the performance timing APIs are enabled.
    */
   static bool IsResourceTimingEnabled()
   {
     return sIsResourceTimingEnabled;
   }
 
   /*
+   * Returns true if the performance timing APIs are enabled.
+   */
+  static bool IsPerformanceNavigationTimingEnabled()
+  {
+    return sIsPerformanceNavigationTimingEnabled;
+  }
+
+  /*
    * Returns true if notification should be sent for peformance timing events.
    */
   static bool SendPerformanceTimingNotifications()
   {
     return sSendPerformanceTimingNotifications;
   }
 
   /*
@@ -3335,16 +3343,17 @@ private:
   static bool sAllowXULXBL_for_file;
   static bool sIsFullScreenApiEnabled;
   static bool sIsUnprefixedFullscreenApiEnabled;
   static bool sTrustedFullScreenOnly;
   static bool sIsCutCopyAllowed;
   static uint32_t sHandlingInputTimeout;
   static bool sIsPerformanceTimingEnabled;
   static bool sIsResourceTimingEnabled;
+  static bool sIsPerformanceNavigationTimingEnabled;
   static bool sIsUserTimingLoggingEnabled;
   static bool sIsFrameTimingPrefEnabled;
   static bool sIsFormAutofillAutocompleteEnabled;
   static bool sIsWebComponentsEnabled;
   static bool sIsCustomElementsEnabled;
   static bool sDevToolsEnabled;
   static bool sSendPerformanceTimingNotifications;
   static bool sUseActivityCursor;

--- a/dom/performance/PerformanceMainThread.cpp
+++ b/dom/performance/PerformanceMainThread.cpp
@@ -307,17 +307,17 @@ DOMHighResTimeStamp
 PerformanceMainThread::CreationTime() const
 {
   return GetDOMTiming()->GetNavigationStart();
 }
 
 void
 PerformanceMainThread::EnsureDocEntry()
 {
-  if (!mDocEntry) {
+  if (!mDocEntry && nsContentUtils::IsPerformanceNavigationTimingEnabled()) {
     nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(mChannel);
     mDocEntry = new PerformanceNavigationTiming(Timing(), this,
                                                 httpChannel);
   }
 }
 
 
 void

--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -158,16 +158,19 @@ pref("dom.serviceWorkers.idle_extended_t
 pref("dom.serviceWorkers.testUpdateOverOneDay", false);
 
 // Whether nonzero values can be returned from performance.timing.*
 pref("dom.enable_performance", true);
 
 // Whether resource timing will be gathered and returned by performance.GetEntries*
 pref("dom.enable_resource_timing", true);
 
+// Whether performance.GetEntries* will contain an entry for the active document
+pref("dom.enable_performance_navigation_timing", true);
+
 // Enable printing performance marks/measures to log
 pref("dom.performance.enable_user_timing_logging", false);
 
 // Enable notification of performance timing
 pref("dom.performance.enable_notify_performance_timing", false);
 
 // Enable Permission API's .revoke() method
 pref("dom.permissions.revoke.enable", false);