title: If the Server responds in text/html type, will the Client not recognize it?
body: <p>I tried to erase jwt token using localStorage.removeItem() function, but failed as a result of running the code below.</p>
  
  <p>I'm coding using Javascript and Express.js in Visual Studio Code.
  And use the Chrome browser.</p>
  
  <p>[Client]</p>
  
  <pre><code>secession = () =&gt; {
    fetch('http://localhost:3000/users/secession', {
      headers: {
        'Content-Type': 'application/json',
        'accessToken': JSON.stringify(localStorage.getItem('tokenValue')),
      }
    })
    .then((result) =&gt; {
      return result.json();
    })
    .then((data) =&gt; {
      if (data === 'success secession') {
        localStorage.removeItem('tokenValue');
        alert('Success');
      } else {
        alert('Fail. Try again');
      }
    })
    .catch((err) =&gt; err);
  }
  </code></pre>
  
  <p>[Server]</p>
  
  <pre><code>secession: async (req, res) =&gt; {
    try {
      const token = req.get('accessToken');
      if (typeof token !== 'undefined') {
        const decoded = jwt.verify(JSON.parse(token), secretKey);
        const result = await users.users.secession(decoded);
        // result is 'success secession' 
        res.send(result);
      } else {
        res.sendStatus(403);
      }
    } catch (err) {
      res.send(err);
    }
  }
  </code></pre>
  
  <p>When I change <strong>res.send(result)</strong> to <strong>res.json(result)</strong> on the Server, I succeeded in erasing the token. </p>
  
  <p>I think the Client doesn't receive the response if Server send <em>result</em> by text/html.</p>
  
  <p>But I'm not sure this is right.</p>