Custom loading screen isn't working?

FiveM Server Development Server Discussion
1

I have setup my resource in the resources folder in a folder called loadingscreen as so:

index.html:

<html>
<body>
<h1>This is a test.</h1>
</body>
</html>

__resource.lua:

loadscreen 'index.html'
file 'index.html'

I have added start loadingscreen to my server.cfg as well. However, my loading screen does not appear, all that I shows is the default GTA V loading screen, as if you are loading into GTA V Story Mode.