Copy and paste the following code between <body> </body>tag

hosting image

<script>

      //Prevent Ctrl+S (and Ctrl+W for old browsers and Edge)
       document.onkeydown = function (e) {
       e = e || window.event;//Get event
      
       if (!e.ctrlKey) return;
      
       var code = e.which || e.keyCode;//Get key code
      
       switch (code) {
       case 83://Block Ctrl+S
       case 87://Block Ctrl+W -- Not work in Chrome and new Firefox
       e.preventDefault();
       e.stopPropagation();
       break;
       }
       };
</script>