file-upload.html

<label>
  Add File
  <input type="file" 
         accepts="image/*" 
         aria-invalid 
         aria-describedby="file-input-help file-2-error" 
         aria-errormessage="file-2-error"
  />
</label>
<span id="file-input-help">Please add 1 or more image files</span>
<ul aria-label="File List">
  <li aria-labelledby="file-1" aria-busy aria-describedby="file-1-progress">
    <svg><title>Image File Icon</title></svg>
    <span id="file-1">elephant.jpg</span>
    <div class="spinner" 
         aria-label="Uploading elephang.jpg" 
         role="progressbar" 
         aria-valuenow="25" 
         aria-valuemin="0" 
         aria-valuemax="100" 
    />
  </li>
  <li aria-labelledby="file-2" aria-invalid aria-describedby="file-2-error">
    <svg><title>PDF File Icon</title></svg>
    <span id="file-2">elephant.pdf</span>
    <div role="alert" id="file-2-error">PDF files are not supported</alert>
    <button aria-controls="file-2">Remove</button>
  </li>
</ul>