Twigs documentation for extensions show that it is possible to use "is_safe" with both simple_filters and and simple_functions, to prevent escaping of html tags in returned values, but I can see any examples of using is_safe with globals. Is there a way to do this?
If your global is pure HTML that needs to be rendered like HTML you could mark it as safe by using
$twig->addGlobal('my_html', new Twig_Markup($html, 'UTF-8'));
If the global is an object and returns the HTML you wrap your return value with a new