Hi Stuart,
Greetings from Syncfusion support.
We are able to reproduce the reported issue. The issue occurred due to a failure in publishing the last weekly NuGet release (19.3.0.44). However, the fix for the issue will be available in our upcoming weekly NuGet release on October 13th, 2021. Sorry for the inconvenience.
We appreciate your patience.
Regards,
Shamini