I'm working on a mobile browser-based client as part of a project and I'm trying to inject a text input element into the scene via the DOM APIs. I've declared the document variable and used the createElement() and appendChild() functions to try and get it on the screen, and while it doesn't crash, it also doesn't show up. Any advice?

I installed this plugin, I've got the editor, but I cannot write anything on it. And the project demo is empty when I open it with Superpowers.
Here is where I installed it : resources/app/systems/game/plugins/florentpoujol/ftex.
It's too bad that we cannot create HTML files inside the editor directly...