Adding jQuery UI to Greasemonkey script fails with external CSS file
// @require currently only works with javascript files. That error is from trying to parse CSS as JS.
Use // @resource for CSS files, like so:
// ==UserScript==// @name Test// @namespace rajat.khandelwal// @description Test script// @include http://YOUR_SERVER.COM/YOUR_PATH/*// @require js/jquery-1.6.2.min.js// @require js/jquery-ui-1.8.16.custom.min.js// @resource customCSS css/ui-darkness/jquery-ui-1.8.16.custom.css// @grant GM_addStyle// @grant GM_getResourceText// ==/UserScript==var newCSS = GM_getResourceText ("customCSS");GM_addStyle (newCSS);alert('hi');However, jQuery-UI CSS makes heavy use of background images. Images that are included via relative paths.
To get the maximum effect of jQuery-UI CSS, I no longer recommend adding it via GM_addStyle().
Use an injected <link> as shown in this complete, jQuery-UI example userscript.