}
	synced := make(chan struct{})
	c := slices.Map(cs, func(e Collection[T]) internalCollection[T] {
		return e.(internalCollection[T])
	})
	go func() {
		for _, c := range c {
			if !c.Synced().WaitUntilSynced(o.stop) {
				return
			}
		}
		close(synced)
		log.Infof("%v synced", o.name)
	}()