@t0m While working on this, is there any chance you could expose the full VST3 plugin state? Right now there is no way for hosts to access a plugin’s Vst::IEditController, because ExternalPlugin::getPlatformSpecificData only exposes Vst::IComponent. Among other issues, this makes it impossible to save .vstpreset files, which include state from the Vst::IEditController.
There’s a little more info about this in this thread.