[Worker
][] threads can create reports in the same way that the main thread
does.
Reports will include information on any Workers that are children of the current
thread as part of the workers
section, with each Worker generating a report
in the standard report format.
The thread which is generating the report will wait for the reports from Worker threads to finish. However, the latency for this will usually be low, as both running JavaScript and the event loop are interrupted to generate the report.