Note: After saving, you have to bypass your browser's cache to see the changes. Google Chrome, Firefox, Microsoft Edge and Safari: Hold down the ⇧ Shift key and click the Reload toolbar button. For details and instructions about other browsers, see Wikipedia:Bypass your cache.
// install [[User:Cacycle/wikEd]] in-browser text editor
document.write('<script type="text/javascript" src="'
+ 'http://en.wikipedia.org/w/index.php?title=User:Cacycle/wikEd.js'
+ '&action=raw&ctype=text/javascript"></script>');