Fullscreen transparency for windows

[white-nova]

What about windows transparency in Fullscreeen Mode?

I did a little research and I found this thread of the mainstream sway where this enhancement was declined.

Someone says this is expected "by design" behavior(due to security purposes). Here is the guy provided a patch(which is outdated as far as I understand) and Here is another one who provided more "fresh" version of this patch. By quickly glancing at the patch I think it's not a "Huge problem" to implement such functionality.

It would be great to have the ability to define something like:
for_window[class="foot"] fullscreen_transparency enable

[iguanajuice]

I don't really think this is possible without some serious modifications. When sway renders a full-screen window, it's not rendering anything below it; no wallpaper, no floating windows, no tiling windows. It's just rendering the full-screen window plus any top level shell effects (such as an app launcher).

But I'm not too familiar with sway's codebase, so correct me if I'm wrong.