var xmltext = "<sometag><someothertag></someothertag></sometag>";
var filename = "file.xml";
var pom = document.createElement('a');
var bb = new Blob([xmltext], {type: 'text/plain'});
pom.setAttribute('href', window.URL.createObjectURL(bb));
pom.setAttribute('download', filename);
pom.dataset.downloadurl = ['text/plain', pom.download, pom.href].join(':');
pom.draggable = true;
pom.classList.add('dragout');
pom.click();