app/assets/images/fallbacks/avatar_default.svg
<svg fill="#d4846f" height="24" viewBox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg">
<path d="M12 12c2.21 0 4-1.79 4-4s-1.79-4-4-4-4 1.79-4 4 1.79 4 4 4zm0 2c-2.67 0-8 1.34-8 4v2h16v-2c0-2.66-5.33-4-8-4z"/>
<path d="M0 0h24v24H0z" fill="none"/>
</svg>