I’ve written an LSL script which “serves” custom-generated HTML via a neat trick I discovered. But don’t bust out the champagne just yet — this method is extremely limited, so I don’t expect this to revolutionize HUDs or anything like that. Still, it’s a fun curiosity.
The trick is this: If you use text of the form “data:text/html,[html code here]” as the web URL, Firefox (and maybe other browsers?) will render the HTML code as a web page. For example, visit data:text/html,<html><body><h1>Oh hai!</h1></body></html>