Снимите проверки для IE и Firefox.
Обновленная версия:
function downloadFile(sUrl) {
//iOS devices do not support downloading. We have to inform user about this.
if (/(iP)/g.test(navigator.userAgent)) {
// alert('Your device does not support files downloading. Please try again in desktop browser.');
window.open(sUrl, '_blank');
return false;
}
//Creating new link node.
var link = document.createElement('a');
link.href = sUrl;
link.setAttribute('target','_blank');
if (link.download !== undefined) {
//Set HTML5 download attribute. This will prevent file from opening if supported.
var fileName = sUrl.substring(sUrl.lastIndexOf('/') + 1, sUrl.length);
link.download = fileName;
}
//Dispatching click event.
if (document.createEvent) {
var e = document.createEvent('MouseEvents');
e.initEvent('click', true, true);
link.dispatchEvent(e);
return true;
}
}