hoppscotch/packages/hoppscotch-app/assets/icons/sidebar.svg

<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
  <rect x="3" y="3" width="18" height="18" rx="2" ry="2"></rect>
  <line x1="9" y1="3" x2="9" y2="21"></line>
</svg>