Thanks Ray - yeah, I do remember seeing that and it jogged my memory when I saw the Rect Collection error.
To be clear, this report is for a VST3 SDK Sample Plugin compiled directly from the SDK with no modifications, and not one of my own plugins or GUI objects.
So I think this is an issue for Steinberg first. It also happens in 3 different VST3 hosts from 3 different manufacturers (the user who found this did issue a trouble ticket for Tracktion).
- Will