--- a/browser/extensions/onboarding/test/browser/browser.ini
+++ b/browser/extensions/onboarding/test/browser/browser.ini
@@ -2,10 +2,11 @@
 support-files =
   head.js
 
 [browser_onboarding_accessibility.js]
 [browser_onboarding_notification.js]
 [browser_onboarding_notification_2.js]
 [browser_onboarding_notification_3.js]
 [browser_onboarding_notification_4.js]
+[browser_onboarding_select_default_tour.js]
 [browser_onboarding_tours.js]
 [browser_onboarding_tourset.js]

new file mode 100644
--- /dev/null
+++ b/browser/extensions/onboarding/test/browser/browser_onboarding_select_default_tour.js
@@ -0,0 +1,114 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const OVERLAY_ICON_ID = "#onboarding-overlay-button";
+const PRIVATE_BROWSING_TOUR_ID = "#onboarding-tour-private-browsing";
+const ADDONS_TOUR_ID = "#onboarding-tour-addons";
+const CUSTOMIZE_TOUR_ID = "#onboarding-tour-customize";
+const CLASS_ACTIVE = "onboarding-active";
+
+add_task(async function test_default_tour_open_the_right_page() {
+  resetOnboardingDefaultState();
+  await SpecialPowers.pushPrefEnv({set: [
+    ["browser.onboarding.tour-type", "new"],
+    ["browser.onboarding.tourset-version", 1],
+    ["browser.onboarding.seen-tourset-version", 1],
+    ["browser.onboarding.newtour", "private,addons,customize"],
+  ]});
+
+  let tab = await openTab(ABOUT_NEWTAB_URL);
+  await promiseOnboardingOverlayLoaded(tab.linkedBrowser);
+  await BrowserTestUtils.synthesizeMouseAtCenter(OVERLAY_ICON_ID, {}, tab.linkedBrowser);
+  await promiseOnboardingOverlayOpened(tab.linkedBrowser);
+
+  info("Make sure the default tour is active and open the right page");
+  let { activeNavItemId, activePageId } = await getCurrentActiveTour(tab.linkedBrowser);
+  is(`#${activeNavItemId}`, PRIVATE_BROWSING_TOUR_ID, "default tour is active");
+  is(activePageId, "onboarding-tour-private-browsing-page", "default tour page is shown");
+
+  await BrowserTestUtils.removeTab(tab);
+});
+
+add_task(async function test_first_tour_is_active_by_default() {
+  resetOnboardingDefaultState();
+  await SpecialPowers.pushPrefEnv({set: [
+    ["browser.onboarding.tour-type", "new"],
+    ["browser.onboarding.tourset-version", 1],
+    ["browser.onboarding.seen-tourset-version", 1],
+    ["browser.onboarding.newtour", "private,addons,customize"],
+  ]});
+
+  let tab = await openTab(ABOUT_NEWTAB_URL);
+  await promiseOnboardingOverlayLoaded(tab.linkedBrowser);
+  await BrowserTestUtils.synthesizeMouseAtCenter(OVERLAY_ICON_ID, {}, tab.linkedBrowser);
+  await promiseOnboardingOverlayOpened(tab.linkedBrowser);
+
+  info("Make sure the default tour is selected");
+  let doc = content && content.document;
+  let dom = doc.querySelector(PRIVATE_BROWSING_TOUR_ID);
+  ok(dom.classList.contains(CLASS_ACTIVE), "default tour is selected");
+  let dom2 = doc.querySelector(ADDONS_TOUR_ID);
+  ok(!dom2.classList.contains(CLASS_ACTIVE), "none default tour should not be selected");
+  let dom3 = doc.querySelector(CUSTOMIZE_TOUR_ID);
+  ok(!dom3.classList.contains(CLASS_ACTIVE), "none default tour should not be selected");
+
+  await BrowserTestUtils.removeTab(tab);
+});
+
+add_task(async function test_select_first_uncomplete_tour() {
+  resetOnboardingDefaultState();
+  await SpecialPowers.pushPrefEnv({set: [
+    ["browser.onboarding.tour-type", "new"],
+    ["browser.onboarding.tourset-version", 1],
+    ["browser.onboarding.seen-tourset-version", 1],
+    ["browser.onboarding.newtour", "private,addons,customize"],
+  ]});
+  setTourCompletedState("onboarding-tour-private-browsing", true);
+
+  let tab = await openTab(ABOUT_NEWTAB_URL);
+  await promiseOnboardingOverlayLoaded(tab.linkedBrowser);
+  await BrowserTestUtils.synthesizeMouseAtCenter(OVERLAY_ICON_ID, {}, tab.linkedBrowser);
+  await promiseOnboardingOverlayOpened(tab.linkedBrowser);
+
+  info("Make sure the first uncomplete tour is selected");
+  let doc = content && content.document;
+  let dom = doc.querySelector(PRIVATE_BROWSING_TOUR_ID);
+  ok(!dom.classList.contains(CLASS_ACTIVE), "the first tour is set completed and should not be selected");
+  let dom2 = doc.querySelector(ADDONS_TOUR_ID);
+  ok(dom2.classList.contains(CLASS_ACTIVE), "the first uncomplete tour is selected");
+  let dom3 = doc.querySelector(CUSTOMIZE_TOUR_ID);
+  ok(!dom3.classList.contains(CLASS_ACTIVE), "other tour should not be selected");
+
+  await BrowserTestUtils.removeTab(tab);
+});
+
+add_task(async function test_select_first_tour_when_all_tours_are_complete() {
+  resetOnboardingDefaultState();
+  await SpecialPowers.pushPrefEnv({set: [
+    ["browser.onboarding.tour-type", "new"],
+    ["browser.onboarding.tourset-version", 1],
+    ["browser.onboarding.seen-tourset-version", 1],
+    ["browser.onboarding.newtour", "private,addons,customize"],
+  ]});
+  setTourCompletedState("onboarding-tour-private-browsing", true);
+  setTourCompletedState("onboarding-tour-addons", true);
+  setTourCompletedState("onboarding-tour-customize", true);
+
+  let tab = await openTab(ABOUT_NEWTAB_URL);
+  await promiseOnboardingOverlayLoaded(tab.linkedBrowser);
+  await BrowserTestUtils.synthesizeMouseAtCenter(OVERLAY_ICON_ID, {}, tab.linkedBrowser);
+  await promiseOnboardingOverlayOpened(tab.linkedBrowser);
+
+  info("Make sure the first tour is selected when all tours are completed");
+  let doc = content && content.document;
+  let dom = doc.querySelector(PRIVATE_BROWSING_TOUR_ID);
+  ok(dom.classList.contains(CLASS_ACTIVE), "should be selected when all tours are completed");
+  let dom2 = doc.querySelector(ADDONS_TOUR_ID);
+  ok(!dom2.classList.contains(CLASS_ACTIVE), "other tour should not be selected");
+  let dom3 = doc.querySelector(CUSTOMIZE_TOUR_ID);
+  ok(!dom3.classList.contains(CLASS_ACTIVE), "other tour should not be selected");
+
+  await BrowserTestUtils.removeTab(tab);
+});