Just picking this up again for clarity. I use Plumsail Forms Designer which is installed on a VM. In 2019, I uploaded the Plumsail.Form app to my catalog in this location: https://somespace.sharepoint.com/sites/appcat/AppCatalog/Plumsail.Form.sppkg.
If this space/service will be retired, exactly how should I expect my Forms Designer to work if it can't reach the App Management?
Your comment Most of Plumsail products are SharePoint framework solutions (SPFx packages) and add-in retirement will not affect them. leaves me with the question above. If Plumsail Forms Designer is a SharePoint framework solution, why did I have to use Add-ins/Apps to register it? Maybe I am missing something.
Thank you for any insight you can offer on possible changes I may need to make.