When will scene(openURLContexts) or scene(willConnectTo) have multiple urlContexts?

Both scene(_:openURLContexts) and scene(_:willConnectTo:options:) (through UIScene.ConnectionOptions) are given a Set of UIOpenURLContext's.

I was wondering in what situations would there be more than one UIOpenURLContext? Every implementation I have seen uses urlContexts.first rather than iterating through all of the urlContext's.