title: Vuejs Issue with the second request having 300ms overhead
body: <p>I started learning Vuejs and I saw a strange behavior with the HTTP request to my web server. I'm using axios to make requests.
  I just installed the vue-cli version 3.11 without using the webpack, and I added the config file vue.config.js next to package.json with the following content to proxy my web server</p>
  
  <pre><code>module.exports = {
   devServer: {
    port: 8081,
    proxy: "http://127.0.0.1:8080"
   }
  };
  </code></pre>
  
  <p>Then using axios I'm trying to do a GET request by clicking a button</p>
  
  <pre><code>axios.get(API_URL, {
        headers: {
          Accept: "application/json",
          "Content-Type": "application/json",
          "Cache-Control": "no-cache"
        }
  }).then(response =&gt; {});
  </code></pre>
  
  <p>My web server based on Python and bottle where the API request of fetching users takes between 5ms and 16ms to be processed.
  By opening the browser inspector I saw that on the second request I'm getting an overhead around 300ms, please see below:
  <a href="https://i.stack.imgur.com/3HKcX.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/3HKcX.png" alt="enter image description here"></a></p>
  
  <p>Request and Response parameters
  <a href="https://i.stack.imgur.com/csBwC.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/csBwC.png" alt="enter image description here"></a>
  Anyone has an opinion about this behavior? I searched a bit for vue-cli 3 issues or CORS headers but I did not find anything helpful. Thank you.</p>