We have minimum deployments set to iOS 15 in one of the app for both application and widget target.
When install app in simulator or real device using Xcode 15.4, it works fine in iOS15, iOS16, iOS17 and iOS18 beta.
When install app in simulator or real device, using Xcode 16 beta 6, it works fine in iOS16, iOS17 and iOS18 beta but in iOS 15, our app doesn't show in widget gallery.