diff --git a/browser/app/profile/firefox.js b/browser/app/profile/firefox.js
index 5c26c735722..7f91d648d09 100644
--- a/browser/app/profile/firefox.js
+++ b/browser/app/profile/firefox.js
@@ -454,7 +454,11 @@ pref("browser.preferences.instantApply", false);
 #else
 pref("browser.preferences.instantApply", true);
 #endif
+#ifdef XP_MACOSX
+pref("browser.preferences.animateFadeIn", true);
+#else
 pref("browser.preferences.animateFadeIn", false);
+#endif
 
 pref("browser.download.show_plugins_in_list", true);
 pref("browser.download.hide_plugins_without_extensions", true);
diff --git a/toolkit/content/widgets/preferences.xml b/toolkit/content/widgets/preferences.xml
index 3e071c06f45..749df11173d 100644
--- a/toolkit/content/widgets/preferences.xml
+++ b/toolkit/content/widgets/preferences.xml
@@ -799,7 +799,11 @@
         <![CDATA[
           var psvc = Components.classes["@mozilla.org/preferences-service;1"]
                                .getService(Components.interfaces.nsIPrefBranch);
+#ifdef XP_MACOSX
+          var animate = true;
+#else
           var animate = false;
+#endif
           try {
             animate = psvc.getBoolPref("browser.preferences.animateFadeIn");
           }