"Shadowbolts costume" vs "Shadowbolts uniform"

There’s two tags but I think functionally they might be the same, is this right?
Costume is by far the dominant one, but should it be?

And some images have both!

When is it one but not the other?

Once upon a time, I think shadowbolts costume was for when a pony is dressed up like a Shadowbolt, but not actually supposed to be a Shadowbolts member,

eg. Raindow Dash on Nightmare Night. That’d be why it implies costume.

At this point, I’m not sure there’s functionally any distinction, anymore. For comparison, wonderbolts costume is aliased to wonderbolts uniform.