app/assets/images/flags/1x1/mu.svg
<svg xmlns="http://www.w3.org/2000/svg" id="flag-icon-css-mu" viewBox="0 0 512 512">
<g fill-rule="evenodd">
<path fill="#009f4d" d="M0 384h512v128H0z"/>
<path fill="#151f6d" d="M0 128h512v128H0z"/>
<path fill="#ee2737" d="M0 0h512v128H0z"/>
<path fill="#ffcd00" d="M0 256h512v128H0z"/>
</g>
</svg>