Make sure use strict exsists

Author: MrBlankCoding

src/GM/gm_core.js

@@ -648,7 +648,8 @@
     try {
       await loader.loadScripts(requireUrls);
 
-      const blob = new Blob([userCode], { type: "text/javascript" });
+      const wrappedCode = `(function() {\n'use strict';\n${userCode}\n})();`;
+      const blob = new Blob([wrappedCode], { type: "text/javascript" });
       const blobUrl = URL.createObjectURL(blob);
 
       await new Promise((resolve, reject) => {