fix "fixcode" default prompt

popup.js

@@ -33,7 +33,7 @@ document.addEventListener("DOMContentLoaded", () => {
       id: "fixCode",
       title: "Fix Code",
       prompt:
-        "Improve or fix the following code snippet. Provide the corrected code without adding any personal comments. Only output the corrected code:",
+        "Improve or fix the following code snippet. Provide the corrected code without adding any personal comments. Only output the corrected code, but as text and not as code field:",
       model: "gpt-4o",
     },
   ];