title: Remove U\0000fffc unicode scalar from string
body: <p>I receive an <code>NSAttributedString</code> that contains a <code>NSTextAttachment</code>. I want to remove that attachment, and it looks like it is represented as <code>"\u{ef}"</code> in the string. Printing the unicode scalars of such string, it also seems that unicode scalar for the <code>"\u{ef}"</code> is <code>U\0000fffc</code>.</p>
  
  <p>I tried to do this:</p>
  
  <pre><code>noAttachmentsText = text.replacingOccurrences(of: "\u{ef}", with: "")
  </code></pre>
  
  <p>with no success, so I'm trying by comparing unicode scalars:</p>
  
  <pre><code>var scalars = Array(text.unicodeScalars)
  for scalar in scalars {
     // compare `scalar` to `U\0000fffc`
  }
  </code></pre>
  
  <p>but I'm not able either to succeed in the comparison.
  How could I do this?</p>