@ Random Penguin Let's see, you would have to write something like this:

@Random Penguin Let's see, you would have to write something like this:

function bookface_custom_footer(string &$body)
{
  $t = Renderer::getMarkupTemplate('footer.tpl', 'addon/bookface');
  $html = Renderer::replaceMacros($t, [
    '$global_font' => DI::pConfig()->get($uid, 'bookface_custom', 'global_font');
    ...
  ]);
  $body .= $html;
}

And then the template file itself:

<style type="text/css">:root{
  {{if $global_font}}--global-font-family: {{$global_font}};{{/if}}
  ...
}</style>

And now it doesn't matter what people put in the global_font config value, it should be escaped in the output.