3 dots fade icon

SVG

<svg xmlns="http://www.w3.org/2000/svg" width="1em" height="1em" viewBox="0 0 24 24"><circle cx="4" cy="12" r="3" fill="currentColor"><animate id="SVG7x14Dcom1" fill="freeze" attributeName="opacity" begin="0;SVGqSjG0dUp1.end-0.25s" dur="0.75s" values="1;.2"/></circle><circle cx="12" cy="12" r="3" fill="currentColor" opacity=".4"><animate fill="freeze" attributeName="opacity" begin="SVG7x14Dcom1.begin+0.15s" dur="0.75s" values="1;.2"/></circle><circle cx="20" cy="12" r="3" fill="currentColor" opacity=".3"><animate id="SVGqSjG0dUp1" fill="freeze" attributeName="opacity" begin="SVG7x14Dcom1.begin+0.3s" dur="0.75s" values="1;.2"/></circle></svg>

React

import type { SVGProps } from "react";

export function SvgSpinners3DotsFade(props: SVGProps<SVGSVGElement>) {
  return (
    <svg {...props} xmlns="http://www.w3.org/2000/svg" width="1em" height="1em" viewBox="0 0 24 24"><circle cx="4" cy="12" r="3" fill="currentColor"><animate id="SVG7x14Dcom1" fill="freeze" attributeName="opacity" begin="0;SVGqSjG0dUp1.end-0.25s" dur="0.75s" values="1;.2"/></circle><circle cx="12" cy="12" r="3" fill="currentColor" opacity=".4"><animate fill="freeze" attributeName="opacity" begin="SVG7x14Dcom1.begin+0.15s" dur="0.75s" values="1;.2"/></circle><circle cx="20" cy="12" r="3" fill="currentColor" opacity=".3"><animate id="SVGqSjG0dUp1" fill="freeze" attributeName="opacity" begin="SVG7x14Dcom1.begin+0.3s" dur="0.75s" values="1;.2"/></circle></svg>
  );
}

Vue

<template>
  <svg xmlns="http://www.w3.org/2000/svg" width="1em" height="1em" viewBox="0 0 24 24"><circle cx="4" cy="12" r="3" fill="currentColor"><animate id="SVG7x14Dcom1" fill="freeze" attributeName="opacity" begin="0;SVGqSjG0dUp1.end-0.25s" dur="0.75s" values="1;.2"/></circle><circle cx="12" cy="12" r="3" fill="currentColor" opacity=".4"><animate fill="freeze" attributeName="opacity" begin="SVG7x14Dcom1.begin+0.15s" dur="0.75s" values="1;.2"/></circle><circle cx="20" cy="12" r="3" fill="currentColor" opacity=".3"><animate id="SVGqSjG0dUp1" fill="freeze" attributeName="opacity" begin="SVG7x14Dcom1.begin+0.3s" dur="0.75s" values="1;.2"/></circle></svg>
</template>

CSS

.icon-3-dots-fade {
  width: 24px;
  height: 24px;
  background-color: currentColor;
  -webkit-mask: url("data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%221em%22%20height%3D%221em%22%20viewBox%3D%220%200%2024%2024%22%3E%3Ccircle%20cx%3D%224%22%20cy%3D%2212%22%20r%3D%223%22%20fill%3D%22currentColor%22%20opacity%3D%221%22%3E%3C%2Fcircle%3E%3Ccircle%20cx%3D%2212%22%20cy%3D%2212%22%20r%3D%223%22%20fill%3D%22currentColor%22%20opacity%3D%221%22%3E%3C%2Fcircle%3E%3Ccircle%20cx%3D%2220%22%20cy%3D%2212%22%20r%3D%223%22%20fill%3D%22currentColor%22%20opacity%3D%221%22%3E%3C%2Fcircle%3E%3C%2Fsvg%3E") no-repeat center / contain;
  mask: url("data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%221em%22%20height%3D%221em%22%20viewBox%3D%220%200%2024%2024%22%3E%3Ccircle%20cx%3D%224%22%20cy%3D%2212%22%20r%3D%223%22%20fill%3D%22currentColor%22%20opacity%3D%221%22%3E%3C%2Fcircle%3E%3Ccircle%20cx%3D%2212%22%20cy%3D%2212%22%20r%3D%223%22%20fill%3D%22currentColor%22%20opacity%3D%221%22%3E%3C%2Fcircle%3E%3Ccircle%20cx%3D%2220%22%20cy%3D%2212%22%20r%3D%223%22%20fill%3D%22currentColor%22%20opacity%3D%221%22%3E%3C%2Fcircle%3E%3C%2Fsvg%3E") no-repeat center / contain;
}

This icon is animated. Browsers do not run SVG animation inside a CSS mask, so the rule above uses a still of the drawn icon. Inline the SVG (or use the React/Vue/Svelte snippet) to keep the animation.