1 files changed, 57 insertions, 0 deletions
diff --git a/browser/extensions/webcompat/experiment-apis/aboutConfigPrefs.js b/browser/extensions/webcompat/experiment-apis/aboutConfigPrefs.js
new file mode 100644
index 0000000000..08a4c3d091
--- /dev/null
+++ b/browser/extensions/webcompat/experiment-apis/aboutConfigPrefs.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";
+
+/* global ExtensionAPI, ExtensionCommon, Services, XPCOMUtils */
+
+XPCOMUtils.defineLazyModuleGetters(this, {
+  Services: "resource://gre/modules/Services.jsm",
+});
+
+this.aboutConfigPrefs = class extends ExtensionAPI {
+  getAPI(context) {
+    const EventManager = ExtensionCommon.EventManager;
+    const extensionIDBase = context.extension.id.split("@")[0];
+    const extensionPrefNameBase = `extensions.${extensionIDBase}.`;
+
+    return {
+      aboutConfigPrefs: {
+        onPrefChange: new EventManager({
+          context,
+          name: "aboutConfigPrefs.onUAOverridesPrefChange",
+          register: (fire, name) => {
+            const prefName = `${extensionPrefNameBase}${name}`;
+            const callback = () => {
+              fire.async(name).catch(() => {}); // ignore Message Manager disconnects
+            };
+            Services.prefs.addObserver(prefName, callback);
+            return () => {
+              Services.prefs.removeObserver(prefName, callback);
+            };
+          },
+        }).api(),
+        async getBranch(branchName) {
+          const branch = `${extensionPrefNameBase}${branchName}.`;
+          return Services.prefs.getChildList(branch).map(pref => {
+            const name = pref.replace(branch, "");
+            return { name, value: Services.prefs.getBoolPref(pref) };
+          });
+        },
+        async getPref(name) {
+          try {
+            return Services.prefs.getBoolPref(
+              `${extensionPrefNameBase}${name}`
+            );
+          } catch (_) {
+            return undefined;
+          }
+        },
+        async setPref(name, value) {
+          Services.prefs.setBoolPref(`${extensionPrefNameBase}${name}`, value);
+        },
+      },
+    };
+  }
+};