Are the web requests obtained by APM RUM asynchronous or synchronous?

[EZprogramming (Kourosh)]

I appreciate your feedback!

@vigneshshanmugam

For the former (XHR specifically), we set the span property sync to true /false

So for API calls, is the default value true or false?

@vigneshshanmugam

For the resource requests, we don't use that flag so it's hard to differentiate.

Is there any other way to differentiate using Elastic or any other external tool?