Handle exception when accessing navigator.serviceWorker on sandboxed frames.

src/content/content.js

@@ -198,7 +198,7 @@ ns.on("capabilities", () => {
   }
 
   if (!ns.canScript) {
-
+    try {
       if ("serviceWorker" in navigator && navigator.serviceWorker.controller) {
         (async () => {
           for (let r of await navigator.serviceWorker.getRegistrations()) {
@@ -206,6 +206,9 @@ ns.on("capabilities", () => {
           }
         })();
       }
+    } catch (e) {
+      debug(e);
+    }
     onScriptDisabled();
   }
 

src/content/experiments.js

@@ -0,0 +1,36 @@
+/*
+ * NoScript - a Firefox extension for whitelist driven safe JavaScript execution
+ *
+ * Copyright (C) 2005-2021 Giorgio Maone <https://maone.net>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * This program is free software: you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later
+ * version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+function testBlob() {
+  if ((location.origin === "https://noscript.net" || location.origin === "null" || location.href.startsWith("data:")) && top !== window ) {
+  if (!testBlob.log) testBlob.log = "";
+  testBlob.log += `${document.readyState} - ${document.URL} - Policy: ${JSON.stringify(ns.policy)}<br>`;
+  if (document.body) {
+      document.body.style.backgroundColor = "yellow";
+      let log = document.body.appendChild(document.createElement("div"));
+      log.textContent = testBlob.log;
+      testBlog.log = "";
+    }
+  }
+}
+testBlob();
+addEventListener("DOMContentLoaded", testBlob);
+
+patchWorkers(() => { self.patched = true; console.log("NoScript-patched worker", self, location) }); // DEV_ONLY