--- a/browser/components/migration/tests/browser/browser.ini
+++ b/browser/components/migration/tests/browser/browser.ini
@@ -1,3 +1,8 @@
+[DEFAULT]
+prefs =
+    browser.newtabpage.activity-stream.enabled=false
+    browser.newtabpage.preload=false
+
 [browser_undo_notification.js]
 [browser_undo_notification_wording.js]
 [browser_undo_notification_multiple_dismissal.js]

--- a/browser/components/migration/tests/browser/browser_undo_notification.js
+++ b/browser/components/migration/tests/browser/browser_undo_notification.js
@@ -14,25 +14,16 @@ const kExpectedNotificationId = "automig
 add_task(async function autoMigrationUndoNotificationShows() {
   let getNotification = browser =>
     gBrowser.getNotificationBox(browser).getNotificationWithValue(kExpectedNotificationId);
 
   scope.AutoMigrate.canUndo = () => true;
   let undoCalled;
   scope.AutoMigrate.undo = () => { undoCalled = true };
 
-  // Disable preloaded activity-stream about:newtab for this test to only run on
-  // the tiles version
-  await SpecialPowers.pushPrefEnv({set: [
-    ["browser.newtabpage.activity-stream.enabled", false],
-    ["browser.newtab.preload", false]
-  ]});
-  // Open and close about:newtab to remove any preloaded activity-stream version
-  await BrowserTestUtils.removeTab(await BrowserTestUtils.openNewForegroundTab(gBrowser));
-
   for (let url of ["about:newtab", "about:home"]) {
     undoCalled = false;
     // Can't use pushPrefEnv because of bug 1323779
     Services.prefs.setCharPref("browser.migrate.automigrate.browser", "someunknownbrowser");
     let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, url, false);
     let browser = tab.linkedBrowser;
     if (!getNotification(browser)) {
       info(`Notification for ${url} not immediately present, waiting for it.`);