--- a/browser/base/content/tabbrowser.js
+++ b/browser/base/content/tabbrowser.js
@@ -1759,20 +1759,21 @@ window._gBrowser = {
       browser.setAttribute("preloadedState", "consumed");
       browser.setAttribute("autocompletepopup", "PopupAutoComplete");
     }
 
     return browser;
   },
 
   _isPreloadingEnabled() {
-    // Preloading for the newtab page is enabled when the pref is true
+    // Preloading for the newtab page is enabled when the prefs are true
     // and the URL is "about:newtab". We do not support preloading for
-    // custom newtab URLs.
+    // custom newtab URLs -- only for the default Firefox Home page.
     return Services.prefs.getBoolPref("browser.newtab.preload") &&
+      Services.prefs.getBoolPref("browser.newtabpage.enabled") &&
       !aboutNewTabService.overridden;
   },
 
   _createPreloadBrowser() {
     // Do nothing if we have a preloaded browser already
     // or preloading of newtab pages is disabled.
     if (this._preloadedBrowser || !this._isPreloadingEnabled()) {
       return;

--- a/browser/components/preferences/in-content/tests/browser.ini
+++ b/browser/components/preferences/in-content/tests/browser.ini
@@ -47,16 +47,17 @@ skip-if = os != "win" || (os == "win" &&
 [browser_defaultbrowser_alwayscheck.js]
 [browser_healthreport.js]
 skip-if = true || !healthreport # Bug 1185403 for the "true"
 [browser_homepages_filter_aboutpreferences.js]
 [browser_extension_controlled.js]
 [browser_languages_subdialog.js]
 [browser_layersacceleration.js]
 [browser_masterpassword.js]
+[browser_newtab_menu.js]
 [browser_notifications_do_not_disturb.js]
 [browser_password_management.js]
 [browser_performance.js]
 skip-if = !e10s
 [browser_performance_e10srollout.js]
 skip-if = !e10s
 [browser_performance_non_e10s.js]
 skip-if = e10s

new file mode 100644
--- /dev/null
+++ b/browser/components/preferences/in-content/tests/browser_newtab_menu.js
@@ -0,0 +1,25 @@
+add_task(async function newtabPreloaded() {
+  await openPreferencesViaOpenPreferencesAPI("paneHome", {leaveOpen: true});
+
+  const {contentDocument: doc, contentWindow} = gBrowser;
+  function dispatchMenuItemCommand(menuItem) {
+    const cmdEvent = doc.createEvent("xulcommandevent");
+    cmdEvent.initCommandEvent("command", true, true, contentWindow, 0, false, false, false, false, null, 0);
+    menuItem.dispatchEvent(cmdEvent);
+  }
+
+  const menuHome = doc.querySelector(`#newTabMode menuitem[value="0"]`);
+  const menuBlank = doc.querySelector(`#newTabMode menuitem[value="1"]`);
+  ok(menuHome.selected, "The first item, Home (default), is selected.");
+  ok(gBrowser._isPreloadingEnabled(), "Default Home allows preloading.");
+
+  dispatchMenuItemCommand(menuBlank);
+  ok(menuBlank.selected, "The second item, Blank, is selected.");
+  ok(!gBrowser._isPreloadingEnabled(), "Non-Home prevents preloading.");
+
+  dispatchMenuItemCommand(menuHome);
+  ok(menuHome.selected, "The first item, Home, is selected again.");
+  ok(gBrowser._isPreloadingEnabled(), "Default Home allows preloading again.");
+
+  BrowserTestUtils.removeTab(gBrowser.selectedTab);
+});