1 files changed, 21 insertions, 0 deletions
diff --git a/docshell/test/unit/test_privacy_transition.js b/docshell/test/unit/test_privacy_transition.js
new file mode 100644
index 0000000000..ae1bf71284
--- /dev/null
+++ b/docshell/test/unit/test_privacy_transition.js
@@ -0,0 +1,21 @@
+var gNotifications = 0;
+
+var observer = {
+  QueryInterface: ChromeUtils.generateQI([
+    "nsIPrivacyTransitionObserver",
+    "nsISupportsWeakReference",
+  ]),
+
+  privateModeChanged(enabled) {
+    gNotifications++;
+  },
+};
+
+function run_test() {
+  let windowlessBrowser = Services.appShell.createWindowlessBrowser(true);
+  windowlessBrowser.docShell.addWeakPrivacyTransitionObserver(observer);
+  windowlessBrowser.docShell.setOriginAttributes({ privateBrowsingId: 1 });
+  windowlessBrowser.docShell.setOriginAttributes({ privateBrowsingId: 0 });
+  windowlessBrowser.close();
+  Assert.equal(gNotifications, 2);
+}