1 files changed, 52 insertions, 0 deletions
diff --git a/browser/components/customizableui/test/browser_history_restore_session.js b/browser/components/customizableui/test/browser_history_restore_session.js
new file mode 100644
index 0000000000..a8b9529209
--- /dev/null
+++ b/browser/components/customizableui/test/browser_history_restore_session.js
@@ -0,0 +1,52 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+add_task(async function testRestoreSession() {
+  info("Check history panel's restore previous session button");
+
+  let win = await BrowserTestUtils.openNewBrowserWindow();
+  CustomizableUI.addWidgetToArea(
+    "history-panelmenu",
+    CustomizableUI.AREA_FIXED_OVERFLOW_PANEL
+  );
+  registerCleanupFunction(() => CustomizableUI.reset());
+
+  // We need to make sure the history is cleared before starting the test
+  await Sanitizer.sanitize(["history"]);
+
+  await openHistoryPanel(win.document);
+
+  let restorePrevSessionBtn = win.document.getElementById(
+    "appMenu-restoreSession"
+  );
+
+  Assert.ok(
+    restorePrevSessionBtn.hidden,
+    "Restore previous session button is not visible"
+  );
+  await hideHistoryPanel(win.document);
+
+  BrowserTestUtils.addTab(win.gBrowser, "about:mozilla");
+  await BrowserTestUtils.closeWindow(win);
+
+  win = await BrowserTestUtils.openNewBrowserWindow();
+
+  let lastSession = ChromeUtils.importESModule(
+    "resource:///modules/sessionstore/SessionStore.sys.mjs"
+  )._LastSession;
+  lastSession.setState(true);
+
+  await openHistoryPanel(win.document);
+
+  restorePrevSessionBtn = win.document.getElementById("appMenu-restoreSession");
+  Assert.ok(
+    !restorePrevSessionBtn.hidden,
+    "Restore previous session button is visible"
+  );
+
+  await hideHistoryPanel(win.document);
+  await BrowserTestUtils.closeWindow(win);
+});