indent-fold.js

Hi and sorry for a newbe question …

I don’t understand the function of indent-fold.js , it’s included in the release but it is not used anywhere and there is no documentation or sample of how to use it.
Is it possible to get some help with this ? ideally a sample/code ?

I am trying to figure out the minimum code needed to achieve indent fold as in python mode but on plain text. Is that possible without creating a separate mode ? if yes how ? if not a sample showing a mode that only achieves indent folding without any coloring/etc features will be very useful in general to understand the codemirror mode mechanism.

Thanks you!
Micha

sorry figured it out.
I still a sample of mode that only include indentation will be very educational.
Thanks!

Then what does it do ?