Is the first row of buttons on a double breasted jacket functional

The Art of Looking Good: Buttoning Your Suit Jacket - Joe Button

How long should a suit jacket be from shoulder seam to end of cuff (not including sleeve length)? - Quora

Suit Jacket Button Closure Rules You Should Know

Double-Breasted Suits & Jackets Guide

Why do some men (even some in senior business positions) wear button-down shirts with 3+ buttons undone, so you can see a bunch of their chest hair? - Quora

The Tradition of Never Buttoning the Bottom Button on a Suit

What is the origin of buttons on men's jacket cuffs? I can't see a function for them. - Quora

How should a suit jacket fit when wearing a waistcoat (vest)? - Quora

Can a waistcoat, preferably with a lapel, be worn in a cotillion without a jacket? - Quora

How to add a personal touch to your jacket through customization or embellishments - Quora

Three ways to wear double-breasted with Gentlemanualen

Is the first row of buttons on a double breasted jacket functional or purely ornamental? - Quora