Alternative code[]
// install [[Wikipedia:User:Cacycle/wikEd]] in-browser text editor
mw.loader.load('//en.wikipedia.org/w/index.php?title=User:Cacycle/wikEd.js&action=raw&ctype=text/javascript');
There's such thing as mw.loader.load in MediaWiki, which loads JS and CSS files (CSS needs an extra parameter). – Dentedharp90041tce 10:43, 20 September 2017 (UTC)