JS feature support

[StoneCypher]

Lots of the compelling things one wants to work with in a browser aren't obligatory. For planning's sake, it might be easier for new users if your onboarding documentation mentioned whether facilities were available for developers.

At this time it is not yet clear to me whether it's better to think of Ultralight in the fashion that one thinks of embedding mshtml as a COM control (that is, as a renderer,) or in the fashion of Electron/Tauri (that is, as a platform)

By example, In the MSHTML approach, your storage lives in the exterior C++-or-whatever app, but in Electron, you do your storage with something like the node fs api

I kind of have the impression that it's MSHTML style. But, I should check first, because any of this that's inside JS is suddenly way, way more portable.

For each of these I'm curious whether these things are available, and if so, on which platforms. Some things I'm interested in:

1. WebGL
2. fetch, xmlhttprequest, webtransport, or anything similar
3. The joystick API
4. The pointer API
5. The <audio> element or any alternative
6. The window.localStorage (or .sessionStorage, lol) API
7. The FileSystem API

I kind of expect most of those to be missing, tbh? But I have high hopes about WebGL, and moderate hopes about the Joystick and pointer APIs.

Thanks for your time