Add custom javascript to be run globally from /public/js/custom.js

The key custom_css at /admin/settings has the value /css/custom.css and will load any custom css we put in the file /public/css/custom.css.

How can we accomplish the same for global custom javascript, for example run /public/js/custom.js on all pages, including workplace and search? Not only in pug-forms were we can already add them with

block append formConfig
	script(src='/public/js/lib.js')