(also required by design/codex-php)

This is mostly relevant to the Reader Experience Team's work, though they do not claim to maintain it.

I looked at replacing lightncandy inside includes/Html/TemplateParser.php with supported alternatives like https://github.com/devtheorem/php-handlebars a year ago, but the way it was built by the Web team (as was) makes it pretty much impossible; we'd have to build a new system, migrate all users to it, and then drop the old one, sadly.