Only when using the Edge browser, I'm getting a generic NetworkError (code 19) when calling XMLHttpRequest.send() against an ArcGIS Online REST endpoint. I have an array of feature service URLs, and I loop through the array to query each feature service for its layers. Following is a code snippet:
Array.forEach(featureServiceURLs, lang.hitch(this, function (featureServiceURL) {
var url = featureServiceURL + "/layers?f=json&token=" + token;
var xmlHTTPRequest = new XMLHttpRequest();
xmlHTTPRequest.open("GET", url, false);
xmlHTTPRequest.send();
var response = JSON.parse(xmlHTTPRequest.responseText);
}));
If the array contains only one URL, then everything works fine. If it contains more than one URL, a NetworkError occurs after the first call to XMLHttpRequest.send().
This behaviour is not observed in Chrome or Firefox.