{ Frameless }

XSLT2Processor.importStylesheetURI()

The importStylesheetURI($uri) function returns a Promise and will load the stylesheet (and any includes), resolving the promise when all is done. The argument must be the location of your something.xsl file. Easy does it!

var xslt = new XSLT2Processor

xslt.importStylesheetURI("something.xsl").then(
    function (xslt) {
        var output = xslt.transformToFragment(document)
        document.body.appendChild(output)
    }
)