title: Appending to txt file produces strange characters
body: <p>My code is:</p>
  
  <pre><code>File.AppendAllText(
         @"C: \Users\aalig\Downloads\stok.txt", 
         "text content" + Environment.NewLine, 
         Encoding.UTF8);
  </code></pre>
  
  <p>But after the writing text file looks that - original text goes first correctly (expected), but followed by hieroglyphs instead of "text content":</p>
  
  <p><a href="https://i.stack.imgur.com/jkhcK.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/jkhcK.jpg" alt="Image of invalid text"></a></p>