1 files changed, 31 insertions, 0 deletions
diff --git a/toolkit/mozapps/update/tests/browser/browser_aboutDialog_fc_network_offline.js b/toolkit/mozapps/update/tests/browser/browser_aboutDialog_fc_network_offline.js
new file mode 100644
index 0000000000..9f81573e23
--- /dev/null
+++ b/toolkit/mozapps/update/tests/browser/browser_aboutDialog_fc_network_offline.js
@@ -0,0 +1,31 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Test for About Dialog foreground check for updates which fails, because the
+// browser is in offline mode and `localhost` cannot be resolved.
+add_task(async function aboutDialog_foregroundCheck_network_offline() {
+  info("[OFFLINE] setting Services.io.offline (do not forget to reset it!)");
+  // avoid that real network connectivity changes influence the test execution
+  Services.io.manageOfflineStatus = false;
+  Services.io.offline = true;
+  registerCleanupFunction(() => {
+    info("[ONLINE] Resetting Services.io.offline");
+    Services.io.offline = false;
+    Services.io.manageOfflineStatus = true;
+  });
+
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["network.disable-localhost-when-offline", true],
+      ["network.dns.offline-localhost", false],
+    ],
+  });
+
+  await runAboutDialogUpdateTest({}, [
+    {
+      panelId: "checkingFailed",
+    },
+  ]);
+});