The Repair operator allows you to repair various particle properties.
Flip explicit normals: when selected, any assigned explicit vertex normals will be flipped.
Remove explicit normals: when selected, any assigned explicit vertex normals will be removed.
Resetting the transforms of particles will un-instance their meshes (beacuse a unique new mesh must be generated for each particle in order for each particle’s mesh to be re-oriented relative to their reset transform).