A bookmarklet that will inject an external script in the browser. (minify, uri encode and add to the href prefixed with "javascript:" in your bookmark)

bookmarklet-runner.js

(function() {
  var script = document.createElement('script');
  script.async = 1;
  script.src = '<url to script>';
  document.getElementsByTagName('body')[0].appendChild(script);
})();

can i put userscripts into this

thanks this is helpful https://mrcoles.com/bookmarklet/ this can also help

you can use GM.js https://github.com/Zaidbaidadekalb/-G-M-Executor.js
its also a bookmarklet that will inject an external script in the browser but you can change the code.