docs: @Nonnull
    public static String getXMLTag (final String in)
    {
      final StringBuilder aSB = new StringBuilder ();
      int pos = 1;
      if (in.charAt (1) == '/')
        pos++;
      while (Character.isLetterOrDigit (in.charAt (pos)))
        aSB.append (in.charAt (pos++));
      return aSB.toString ().toLowerCase (Locale.US);
    }