Using withCredentials with type: 'json'

I work with Chris and have picked up this task - so upgrading Flexmonster allows withCredentials to be used for the initial load, but we also need to refresh the underlying data. Using the updateData method appears to be the correct way to go about this, but doing this causes withCredentials to be set to false on the subsequent XmlHttpRequest.
Trying to debug the minified code, the problem seems to be that the data object gets copied in two different ways depending on whether you're using setReport or updateData - the one updateData uses looks like this:

           i9(f) {
             var c = {};
             e.w(f.dataSourceType) || (c.dataSourceType = f.dataSourceType);
             e.w(f.type) || (c.dataSourceType = f.type);
             e.w(f.proxyUrl) || (c.proxyUrl = f.proxyUrl);
             e.w(f.dataSourceInfo) || (c.dataSourceInfo = f.dataSourceInfo);
             e.w(f.catalog) || (c.catalog = f.catalog);
             e.w(f.cube) || (c.cube = f.cube);
             e.w(f.subquery) || (c.subquery = f.subquery);
             e.w(f.localeIdentifier) ||
               (c.localeIdentifier = f.localeIdentifier);
             e.w(f.effectiveUserName) ||
               (c.effectiveUserName = f.effectiveUserName);
             e.w(f.customData) || (c.customData = f.customData);
             e.w(f.filename) || (c.filename = f.filename);
             e.w(f.requestHeader) || (c.requestHeaders = f.requestHeader);
             e.w(f.requestHeaders) || (c.requestHeaders = f.requestHeaders);
             e.w(f.fieldSeparator) || (c.fieldSeparator = f.fieldSeparator);
             e.w(f.thousandSeparator) ||
               (c.thousandSeparator = f.thousandSeparator);
             e.w(f.recordsetDelimiter) ||
               (c.recordsetDelimiter = f.recordsetDelimiter);
             e.w(f.browseForFile) || (c.browseForFile = f.browseForFile);
             e.w(f.data) || (c.data = f.data);
             e.w(f.binary) || (c.binary = f.binary);
             e.w(f.ignoreQuotedLineBreaks) ||
               (c.ignoreQuotedLineBreaks = f.ignoreQuotedLineBreaks);
             e.w(f.roles) || (c.roles = f.roles);
             e.w(f.hash) || (c.hash = f.hash);
             e.w(f.username) || (c.username = f.username);
             e.w(f.password) || (c.password = f.password);
             e.w(f.host) || (c.host = f.host);
             e.w(f.node) || (c.node = f.node);
             e.w(f.index) || (c.index = f.index);
             e.w(f.mapping) || (c.mapping = f.mapping);
             e.w(f.useStreamLoader) || (c.useStreamLoader = f.useStreamLoader);
             e.w(f.url) || (c.url = f.url);
             return c;
           }

As you can see it's copying everything except withCredentials.
Are you able to fix this, and is there any way to work around it in the meantime? I've tried using setReport instead but that has its own set of quirks - namely it causes the field list to appear and reappear even though configuratorActive is always set to true.

Hi Vera  - thanks so much for that, I'll look forward to the release!
For the field list, you can actually see the behaviour I'm describing in your fiddle if you just turn configuratorActive to true - https://jsfiddle.net/z13peLhd/1/. We want the field list to always be shown unless the user specifically hides it (we put it at the right, as per the fiddle link), but every setReport call toggles from hidden to shown or from shown to hidden.

Thanks Vera, we'll give it a go!

Hi Vera,
 
Sorry about the delay, just circled back to this - it works great in the new version, thanks so much for the fix!
 
Thanks,
Alex