Setting .responseType before calling .open() causes InvalidStateError in IE11 #6
Description
The foreign function _xmlHttpRequest sets the response type of xhr before calling .open() on it. In IE11 this causes an InvalidStateError to be thrown. (I can't find any documentation of this, but I have verified that setting the response type before calling open on a new XHR in the console causes this error.)
Would it be possible to change the library so that it doesn't set the response type before calling .open()? I'm happy to make that change if you'd like, though I'm not quite sure how to do that in a backwards-compatible way.