Is it intentional for packages to depend on preview packages?

[ej-hayashi]

Is it intentional that packages such as @fluentui/react-toast include the preview package like @fluentui/react-motion-components-preview in their dependencies?

[MukundaKatta]

Yes — react-toast uses motion components from react-motion-components-preview because motion primitives haven't graduated to stable yet. When they do (it's on the v9 roadmap), the dep will be swapped for the stable package. For now, treat -preview packages consumed transitively as effectively stable for the consuming stable package's API surface — breaking changes in preview are handled at the consumer-package version.