Hi Richard,
Greetings from Syncfusion.
We have validated your reported scenario. We have considered this as a bug and logged a defect report. This fix will be available in our upcoming weekly patch release which is scheduled to be rolled out on 7th July, 2020. We appreciate your patience until then. You can keep track of the bug from the feedback portal below.
The provided feedback link is private, and you need to login to view this feedback.
If you have any more specification/precise replication procedure or a scenario to be tested, you can add it as a comment in the portal.
Regards,
Durga G