Hi Wayne Aronson,
We have fixed the reported "Hiding Thickness Slider after adding a shape on the SFImageEditor" issue and the fix is included in our weekly NuGet of March 16, 2021.
NuGet Version: 18.4.0.48
We thank you for your support and appreciate your patience in waiting for this release. Please get in touch with us if you would require any further assistance.
Regards,
Sridevi S.