Adding another switch to the stack. Got questions.

I recently started a job at another company. On my previous job 90% of my work was routing related, and remote, so im off my bubble here.

Today i got assigned to me a ticket about adding another switch to an existing stack of 3x Catalyst 3850.

I already changed the priorities to make sure the master switch remains the same, and changed the IOS of the new switch to the same as the ones on the stack.

The switch hasnt been added to the stack yet since the stack is on a client.

My question is, do i need to actually configure anything on this 4th switch? Like local user, etc. It just seems too easy if its just like this.