Unfortunately, nowhere on Itch.io's website can I find documentation describing exactly the application protection that you use with them. I mean integrated into your EFPSE editors.

Do you know of any links to this? I would like to use this protection.

Thank you.

Itch doesn't have any copy protection, I had to integrate my own simple one into the editor. 

So what you have to do is use itch.io api when you develop your game and integrate its functions into your source code.