The script checks the ‘SharePoint Online Web Client Extensibility’ Principal within Entra ID for the actual assigned permissions as the SPFx solutions requests are all be added to that single shared permission group. As hilghlighted by “Wes Hackett”: I’ve personally seen plenty of tenants with Mailbox permissions with no corresponding solutions live in the app catalogs. Early SPFx doc examples encouraged the use of MS Graph into Mailbox permissions in one of the how to learn samples, older tenants sometimes have this breadcrumb left behind.