<textarea>Hello, World!</textarea>

<svg xmlns="http://www.w3.org/2000/svg" width="0" height="0">
  <defs>
    <linearGradient id="mygradient" x1="80.86%" x2="19.14%" y1="0%" y2="100%">
      <stop offset="0%" stop-color="#cc208e" />
      <stop offset="100%" stop-color="#6713d2" />
    </linearGradient>
  </defs>
</svg>

<style>
  .tox svg path {
    fill: url(#mygradient);
  }
</style>

tinymce.init({
  selector: "textarea",
  menubar: false,
  plugins: [
    "advlist autolink lists link image charmap print preview anchor",
    "searchreplace visualblocks code fullscreen",
    "insertdatetime media table paste"
  ],
  toolbar:
    "insertfile undo redo | bold italic | alignleft aligncenter alignright alignjustify | bullist numlist outdent indent | link image"
});