diff --git a/gfx/thebes/gfxMacPlatformFontList.h b/gfx/thebes/gfxMacPlatformFontList.h
index 1729e8df9113..9c26b5ccbf6c 100644
--- a/gfx/thebes/gfxMacPlatformFontList.h
+++ b/gfx/thebes/gfxMacPlatformFontList.h
@@ -6,6 +6,8 @@
 #ifndef gfxMacPlatformFontList_H_
 #define gfxMacPlatformFontList_H_
 
+#include <CoreFoundation/CoreFoundation.h>
+
 #include "mozilla/MemoryReporting.h"
 #include "nsDataHashtable.h"
 #include "nsRefPtrHashtable.h"
@@ -14,8 +16,6 @@
 #include "gfxPlatform.h"
 #include "gfxPlatformMac.h"
 
-#include <Carbon/Carbon.h>
-
 #include "nsUnicharUtils.h"
 #include "nsTArray.h"
 
@@ -101,7 +101,11 @@ private:
     // special case font faces treated as font families (set via prefs)
     void InitSingleFaceList();
 
-    static void ATSNotification(ATSFontNotificationInfoRef aInfo, void* aUserArg);
+    static void RegisteredFontsChangedNotificationCallback(CFNotificationCenterRef center,
+                                                           void *observer,
+                                                           CFStringRef name,
+                                                           const void *object,
+                                                           CFDictionaryRef userInfo);
 
     // search fonts system-wide for a given character, null otherwise
     virtual gfxFontEntry* GlobalFontFallback(const uint32_t aCh,
@@ -112,9 +116,6 @@ private:
 
     virtual bool UsesSystemFallback() { return true; }
 
-    // keep track of ATS generation to prevent unneeded updates when loading downloaded fonts
-    uint32_t mATSGeneration;
-
     enum {
         kATSGenerationInitial = -1
     };
diff --git a/gfx/thebes/gfxMacPlatformFontList.mm b/gfx/thebes/gfxMacPlatformFontList.mm
index b37359f68cad..b03556e6c619 100644
--- a/gfx/thebes/gfxMacPlatformFontList.mm
+++ b/gfx/thebes/gfxMacPlatformFontList.mm
@@ -43,7 +43,6 @@
 #endif
 #include "prlog.h"
 
-#include <Carbon/Carbon.h>
 #include <algorithm>
 
 #import <AppKit/AppKit.h>
@@ -646,12 +645,15 @@ gfxSingleFaceMacFontFamily::ReadOtherFamilyNames(gfxPlatformFontList *aPlatformF
 #pragma mark-
 
 gfxMacPlatformFontList::gfxMacPlatformFontList() :
-    gfxPlatformFontList(false), mATSGeneration(uint32_t(kATSGenerationInitial)),
+    gfxPlatformFontList(false),
     mDefaultFont(nullptr)
 {
-    ::ATSFontNotificationSubscribe(ATSNotification,
-                                   kATSFontNotifyOptionDefault,
-                                   (void*)this, nullptr);
+    ::CFNotificationCenterAddObserver(::CFNotificationCenterGetLocalCenter(),
+                                      this,
+                                      RegisteredFontsChangedNotificationCallback,
+                                      kCTFontManagerRegisteredFontsChangedNotification,
+                                      0,
+                                      CFNotificationSuspensionBehaviorDeliverImmediately);
 
     // cache this in a static variable so that MacOSFontFamily objects
     // don't have to repeatedly look it up
@@ -670,19 +672,8 @@ gfxMacPlatformFontList::InitFontList()
 {
     nsAutoreleasePool localPool;
 
-    ATSGeneration currentGeneration = ::ATSGetGeneration();
-
-    // need to ignore notifications after adding each font
-    if (mATSGeneration == currentGeneration)
-        return NS_OK;
-
     Telemetry::AutoTimer<Telemetry::MAC_INITFONTLIST_TOTAL> timer;
 
-    mATSGeneration = currentGeneration;
-#ifdef PR_LOGGING
-    LOG_FONTLIST(("(fontlist) updating to generation: %d", mATSGeneration));
-#endif
-
     // reset font lists
     gfxPlatformFontList::InitFontList();
     
@@ -777,11 +768,18 @@ gfxMacPlatformFontList::GetStandardFamilyName(const nsAString& aFontName, nsAStr
 }
 
 void
-gfxMacPlatformFontList::ATSNotification(ATSFontNotificationInfoRef aInfo,
-                                        void* aUserArg)
+gfxMacPlatformFontList::RegisteredFontsChangedNotificationCallback(CFNotificationCenterRef center,
+                                                                   void *observer,
+                                                                   CFStringRef name,
+                                                                   const void *object,
+                                                                   CFDictionaryRef userInfo)
 {
+    if (!::CFEqual(name, kCTFontManagerRegisteredFontsChangedNotification)) {
+        return;
+    }
+
     // xxx - should be carefully pruning the list of fonts, not rebuilding it from scratch
-    static_cast<gfxMacPlatformFontList*>(aUserArg)->UpdateFontList();
+    static_cast<gfxMacPlatformFontList*>(observer)->UpdateFontList();
 
     // modify a preference that will trigger reflow everywhere
     static const char kPrefName[] = "font.internaluseonly.changed";