javascript - Setting XMLHttpRequest.responseType forbidden all of a sudden?

Question

I've been using synchronous XMLHttpRequest with responseType set to "arraybuffer" for quite a while to load a binary file and wait until it is loaded. Today, I got this error: "Die Verwendung des responseType-Attributes von XMLHttpRequest wird im synchronen Modus im window-Kontekt nicht mehr unterstützt." which roughly translates to "Usage of responseType for XMLHttpRequest in synchronous mode in window-context(?) no longer supported."

Does anyone know how to fix this? I realy don't want to use an asynchronous request for something like this.

var xhr = new XMLHttpRequest();
xhr.open('GET', url, false);
xhr.responseType = 'arraybuffer';

Works fine in chrome.

Answer 1

This is correct behaviour, as defined in the Specification of XMLHttpRequest:

When set: throws an "InvalidAccessError" exception if the synchronous flag is set and there is an associated XMLHttpRequest document.

The responseType property cannot be set when the XMLHttpRequest is not async, that is, synchronous. Setting the third parameter of open to false causes the request to be synchronous.