1 files changed, 58 insertions, 0 deletions
diff --git a/browser/base/content/test/about/browser_bug435325.js b/browser/base/content/test/about/browser_bug435325.js
new file mode 100644
index 0000000000..70a3b272a9
--- /dev/null
+++ b/browser/base/content/test/about/browser_bug435325.js
@@ -0,0 +1,58 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/* Ensure that clicking the button in the Offline mode neterror page makes the browser go online. See bug 435325. */
+
+add_task(async function checkSwitchPageToOnlineMode() {
+  // Go offline and disable the proxy and cache, then try to load the test URL.
+  Services.io.offline = true;
+
+  // Tests always connect to localhost, and per bug 87717, localhost is now
+  // reachable in offline mode.  To avoid this, disable any proxy.
+  let proxyPrefValue = SpecialPowers.getIntPref("network.proxy.type");
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["network.proxy.type", 0],
+      ["browser.cache.disk.enable", false],
+      ["browser.cache.memory.enable", false],
+    ],
+  });
+
+  await BrowserTestUtils.withNewTab("about:blank", async function (browser) {
+    let netErrorLoaded = BrowserTestUtils.waitForErrorPage(browser);
+
+    // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+    BrowserTestUtils.loadURIString(browser, "http://example.com/");
+    await netErrorLoaded;
+
+    // Re-enable the proxy so example.com is resolved to localhost, rather than
+    // the actual example.com.
+    await SpecialPowers.pushPrefEnv({
+      set: [["network.proxy.type", proxyPrefValue]],
+    });
+    let changeObserved = TestUtils.topicObserved(
+      "network:offline-status-changed"
+    );
+
+    // Click on the 'Try again' button.
+    await SpecialPowers.spawn(browser, [], async function () {
+      ok(
+        content.document.documentURI.startsWith("about:neterror?e=netOffline"),
+        "Should be showing error page"
+      );
+      content.document
+        .querySelector("#netErrorButtonContainer > .try-again")
+        .click();
+    });
+
+    await changeObserved;
+    ok(
+      !Services.io.offline,
+      "After clicking the 'Try Again' button, we're back online."
+    );
+  });
+});
+
+registerCleanupFunction(function () {
+  Services.io.offline = false;
+});