code: function () {
  				return Array.from(document.styleSheets).filter(function (styleSheet) {
  					var themeName = sap.ui.getCore().getConfiguration().getTheme(),
  						styleSheetEnding = "/themes/" + themeName + "/library.css",
  						hasHref = !styleSheet.href || !(styleSheet.href.indexOf(styleSheetEnding) !== -1),
  						hasRules = !!styleSheet.rules;
  
  					return hasHref && hasRules;
  				});
  			}
docs: *
  Search and filter all style sheets that are not loaded by the default theme and controls.
  @returns {array} List of all custom CSS files paths.