1 files changed, 36 insertions, 0 deletions
diff --git a/browser/base/content/test/favicons/browser_missing_favicon.js b/browser/base/content/test/favicons/browser_missing_favicon.js
new file mode 100644
index 0000000000..40dce7f7a9
--- /dev/null
+++ b/browser/base/content/test/favicons/browser_missing_favicon.js
@@ -0,0 +1,36 @@
+add_task(async () => {
+  let testPath = getRootDirectory(gTestPath);
+
+  // The default favicon would interfere with this test.
+  Services.prefs.setBoolPref("browser.chrome.guess_favicon", false);
+  registerCleanupFunction(() => {
+    Services.prefs.setBoolPref("browser.chrome.guess_favicon", true);
+  });
+
+  await BrowserTestUtils.withNewTab(
+    { gBrowser, url: "about:blank" },
+    async browser => {
+      const expectedIcon = testPath + "file_generic_favicon.ico";
+      let faviconPromise = waitForLinkAvailable(browser);
+
+      BrowserTestUtils.loadURIString(
+        browser,
+        testPath + "file_with_favicon.html"
+      );
+      await BrowserTestUtils.browserLoaded(browser);
+
+      let iconURI = await faviconPromise;
+      is(iconURI, expectedIcon, "Got correct icon.");
+
+      BrowserTestUtils.loadURIString(browser, testPath + "blank.html");
+      await BrowserTestUtils.browserLoaded(browser);
+
+      is(browser.mIconURL, null, "Should have blanked the icon.");
+      is(
+        gBrowser.getTabForBrowser(browser).getAttribute("image"),
+        "",
+        "Should have blanked the tab icon."
+      );
+    }
+  );
+});