1 files changed, 44 insertions, 0 deletions
diff --git a/browser/extensions/webcompat/shims/kinja.js b/browser/extensions/webcompat/shims/kinja.js
new file mode 100644
index 0000000000..d30425b42d
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+++ b/browser/extensions/webcompat/shims/kinja.js
@@ -0,0 +1,44 @@
+/* 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/. */
+
+/* globals exportFunction */
+
+"use strict";
+
+/**
+ * Kinja powered blogs rely on storage access to https://kinja.com to enable
+ * oauth with external providers. For dFPI, sites need to use the Storage Access
+ * API to gain first party storage access. This shim calls requestStorageAccess
+ * on behalf of the site when a user wants to log in via oauth.
+ */
+
+// Third-party origin we need to request storage access for.
+const STORAGE_ACCESS_ORIGIN = "https://kinja.com";
+
+// Prefix of the path opened in a new window when users click the oauth login
+// buttons.
+const OAUTH_PATH_PREFIX = "/oauthlogin?provider=";
+
+console.warn(
+  `When using oauth, Firefox calls the Storage Access API on behalf of the site. See https://bugzilla.mozilla.org/show_bug.cgi?id=1656171 for details.`
+);
+
+// Overwrite the window.open method so we can detect oauth related popups.
+const origOpen = window.wrappedJSObject.open;
+Object.defineProperty(window.wrappedJSObject, "open", {
+  value: exportFunction((url, ...args) => {
+    // Filter oauth popups.
+    if (!url.startsWith(OAUTH_PATH_PREFIX)) {
+      return origOpen(url, ...args);
+    }
+    // Request storage access for Kinja.
+    document.requestStorageAccessForOrigin(STORAGE_ACCESS_ORIGIN).then(() => {
+      origOpen(url, ...args);
+    });
+    // We don't have the window object yet which window.open returns, since the
+    // sign-in flow is dependent on the async storage access request. This isn't
+    // a problem as long as the website does not consume it.
+    return null;
+  }, window),
+});