JSFiddle - React, Tailwind, and code Playground

HTML

<div>
  <img src="http://www.iconsdb.com/icons/download/black/square-16.png">
  <textarea></textarea>
</div>

CSS

div {
  position: relative;
  width: 400px;
}

img {
  position: absolute;
  bottom: 4px;
  right: 0;
  z-index: 1;
  pointer-events: none;
}

textarea {
  resize: vertical;
  width: 100%;
  border: 0 none;
  padding: 0;
  min-height: 100px;
}