--- a/browser/app/profile/firefox.js
+++ b/browser/app/profile/firefox.js
@@ -909,16 +909,24 @@ pref("browser.sessionstore.debug.no_auto
 // Forget closed windows/tabs after two weeks
 pref("browser.sessionstore.cleanup.forget_closed_after", 1209600000);
 // Maximum number of bytes of DOMSessionStorage data we collect per origin.
 pref("browser.sessionstore.dom_storage_limit", 2048);
 
 // allow META refresh by default
 pref("accessibility.blockautorefresh", false);
 
+// Whether useAsyncTransactions is enabled or not.
+// Currently we only enable them for nightly.
+#ifdef NIGHTLY_BUILD
+pref("browser.places.useAsyncTransactions", true);
+#else
+pref("browser.places.useAsyncTransactions", false);
+#endif
+
 // Whether history is enabled or not.
 pref("places.history.enabled", true);
 
 // the (maximum) number of the recent visits to sample
 // when calculating frecency
 pref("places.frecency.numVisits", 10);
 
 // buckets (in days) for frecency calculation