For the latest list of Flutter’s widgets that
are affected by the useMaterial3 flag, see
Affected widgets.

The vast majority of Flutter widgets have similar
behavior in M2 and M3, so those widget names are unchanged.
However, a couple widgets have substantially different
behavior in M3, so new widgets have been created.

Once migration is complete, Material 3 will
become the Material library’s default look and feel.

Support for Material 2 will eventually be removed according
to Flutter’s deprecation policy.

Explore the updated components, typography, color system,
and elevation support with the
interactive Material 3 demo:

More information

To learn more about Material Design and Flutter,
check out:

Material.io developer documentation

Migrating a Flutter app to Material 3 blog post by Taha Tesser