ajax failed in IE8

webix.ajax.$callback = function(owner, call, text, data, x, is_error){
	if (owner.$destructed) return;
	if (x == -1 && data && typeof data.json == "function")
		data = data.json();

Can you share a peace of code that initiated ajax operation ?
And if possible - full text of error message from IE dev tools console.

Ajax operations works fine for default samples, so it must be something specific in the way how ajax used in the problematic case.

x == -1 not supported in IE8

I can confirm issue. Fix will be included in the next build

If you have an active license, you can grab Webix 2.1.4 from the support area. It contains a fix for the above issue.

Thank you, issue fiexed