1 files changed, 57 insertions, 0 deletions
diff --git a/browser/extensions/webcompat/shims/tsn-ca.js b/browser/extensions/webcompat/shims/tsn-ca.js
new file mode 100644
index 0000000000..ee8e96b661
--- /dev/null
+++ b/browser/extensions/webcompat/shims/tsn-ca.js
@@ -0,0 +1,57 @@
+/* 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";
+
+/*
+ * Bug 1802340 - tsn.ca login broken with dFPI enabled
+ *
+ * tsn.ca relies upon a login page that is out-of-origin. That login page
+ * sets a cookie for https://www.tsn.ca, which is then used as an proof of
+ * authentication on redirect back to the main site. This shim adds a request
+ * for storage access for https://www.tsn.ca when the user tries to log in.
+ */
+
+console.warn(
+  `When logging in, Firefox calls the Storage Access API on behalf of the site. See https://bugzilla.mozilla.org/show_bug.cgi?id=1802340 for details.`
+);
+
+// Third-party origin we need to request storage access for.
+const STORAGE_ACCESS_ORIGIN = "https://www.tsn.ca";
+
+document.documentElement.addEventListener(
+  "click",
+  e => {
+    const { target, isTrusted } = e;
+    if (!isTrusted) {
+      return;
+    }
+
+    const button = target.closest("button");
+    if (!button) {
+      return;
+    }
+    const form = target.closest(".login-form");
+    if (!form) {
+      return;
+    }
+
+    console.warn(
+      "Calling the Storage Access API on behalf of " + STORAGE_ACCESS_ORIGIN
+    );
+    button.disabled = true;
+    e.stopPropagation();
+    e.preventDefault();
+    document
+      .requestStorageAccessForOrigin(STORAGE_ACCESS_ORIGIN)
+      .then(() => {
+        button.disabled = false;
+        target.click();
+      })
+      .catch(() => {
+        button.disabled = false;
+      });
+  },
+  true
+);