Hi kofi,

By default, Mendix generates the index.html (the page that is loaded to start the app), based on the app configuration. In some cases it may be needed to customize this HTML, which can be done by creating a file called index.html in the theme/web folder. To make sure that your file has the right structure, we recommend you copy index-example.html from the deployment/web folder to the theme/web, rename it to index.html, and then use it as a starting point. This file will be created after you have deployed your app locally at least once.

Refer below link(Point no-9)  :- https://docs.mendix.com/howto/front-end/customize-styling-new

After help of a collegue, it works fine. 

This stuff will be cached immediately so its really hard to test this. Golden tip: try this in incognito screen.

Hi, 

I have implemented this, but without success. I did the following:

- create a new app (so no risks)
- Run the app (Mx9.9.1)
- navigate to ..\deployment\web
- copy index-example.html
- navigate to ..\theme\web
- paste the file
- rename it to index.html
- make changes
- save changes
- back to the add
- press F4 (Synchronise with file system, perhaps this is not needed)
- run app
- check index.html file in ..\deployment\web 
- changes are correct in this file
- test in the browser
- doens'nt work

My change was to check if the browser is near the latest version. Purpose was to check if Firefox does have the near latest version. Currently it is version 95 and I test this with version 93. i did the same test with Mendix 8, this works fine. 

Script:
<script> 
var $buoop = {required:{e:-4,f:0,o:-3,s:-1,c:-3},insecure:true,api:2022.01 }; 
function $buo_f(){ 
 var e = document.createElement("script"); 
 e.src = "//browser-update.org/update.min.js"; 
 document.body.appendChild(e);
};
try {document.addEventListener("DOMContentLoaded", $buo_f,false)}
catch(e){window.attachEvent("onload", $buo_f)}
</script>