metamask-extension/ui/components/multichain/multichain-connected-site-menu/index.scss

.multichain-connected-site-menu {
  &__badge {
    height: 16px;
    width: 16px;
  }

  &__badge.not-connected {
    height: 10px;
    width: 10px;
  }

  &__badge.not-connected::after {
    content: '';
    position: absolute;
    top: -3px;
    left: -3px;
    right: -3px;
    bottom: -3px;
    background: var(--color-background-default);
    z-index: -1;
    border-radius: 50%;
  }
}