I don't think so. The HTML5 parsing spec is very precise now, and browsers follow it. To my knowledge, how you parse an HTML document is now very well defined.
Plus, JSX isn't even served to browsers at all. Now, I don't agree with the parent that it's wrong that JSX parses differently than HTML. They got rid of the issues caused by indentation and spacing code ending up meaning something and causing a different rendering than non spaced HTML document, which is a good thing. It could also totally be fixed if needed, you define version of your dependencies in charge of interpreting it. HTML is the "unfixable" one.
Plus, JSX isn't even served to browsers at all. Now, I don't agree with the parent that it's wrong that JSX parses differently than HTML. They got rid of the issues caused by indentation and spacing code ending up meaning something and causing a different rendering than non spaced HTML document, which is a good thing. It could also totally be fixed if needed, you define version of your dependencies in charge of interpreting it. HTML is the "unfixable" one.