title: What's the different between txt and QTextEdit about their style
body: <p>When I copy the content from txt to the QTextEdit, I find the style of the content has changed.I'm so puzzled.Is this the reason for coding?How can I solve it?(System: Mac OS)</p>
  
  <p><a href="https://i.stack.imgur.com/FxiIw.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/FxiIw.jpg" alt="enter image description here"></a></p>