--- a/browser/app/profile/firefox.js
+++ b/browser/app/profile/firefox.js
@@ -1875,22 +1875,19 @@ pref("dom.ipc.processHangMonitor", true)
 #ifdef DEBUG
 // Don't report hangs in DEBUG builds. They're too slow and often a
 // debugger is attached.
 pref("dom.ipc.reportProcessHangs", false);
 #else
 pref("dom.ipc.reportProcessHangs", true);
 #endif
 
-// Enable ReadingList browser UI by default.
-pref("browser.readinglist.enabled", true);
+pref("browser.readinglist.enabled", false);
 pref("browser.readinglist.sidebarEverOpened", false);
-
-// Enable the readinglist engine by default.
-pref("readinglist.scheduler.enabled", true);
+pref("readinglist.scheduler.enabled", false);
 pref("readinglist.server", "https://readinglist.services.mozilla.com/v1");
 
 // Don't limit how many nodes we care about on desktop:
 pref("reader.parse-node-limit", 0);
 
 // Enable Service workers for desktop on non-release builds
 #ifdef NIGHTLY_BUILD
 pref("dom.serviceWorkers.enabled", true);

--- a/browser/components/readinglist/test/xpcshell/test_scheduler.js
+++ b/browser/components/readinglist/test/xpcshell/test_scheduler.js
@@ -10,16 +10,17 @@ Services.prefs.setCharPref("readinglist.
 let {createTestableScheduler} = Cu.import("resource:///modules/readinglist/Scheduler.jsm", {});
 Cu.import("resource://gre/modules/Preferences.jsm");
 Cu.import("resource://gre/modules/Timer.jsm");
 
 // Log rotation needs a profile dir.
 do_get_profile();
 
 let prefs = new Preferences("readinglist.scheduler.");
+prefs.set("enabled", true);
 
 function promiseObserver(topic) {
   return new Promise(resolve => {
     let obs = (subject, topic, data) => {
       Services.obs.removeObserver(obs, topic);
       resolve(data);
     }
     Services.obs.addObserver(obs, topic, false);