<h4 dir="auto">Describe the bug</h4>
<p dir="auto">When using <code class="notranslate">axios.create</code>, if I pass a custom property it is not being visible on the interceptors.</p>
<h4 dir="auto">To Reproduce</h4>
<p dir="auto">Something like:</p>
<div class="highlight highlight-source-js notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="const instance = axios.create({
      baseURL: 'http://myurl.com',
      withCredentials: false,
      loader: true // Custom property
});

instance.interceptors.request.use(
      config =&gt; {
        console.log('request', config); // Does not show the &quot;loader&quot; property

        if (config.loader) {
          showLoader();
        }

        return config;
      }
);"><pre class="notranslate"><span class="pl-k">const</span> <span class="pl-s1">instance</span> <span class="pl-c1">=</span> <span class="pl-s1">axios</span><span class="pl-kos">.</span><span class="pl-en">create</span><span class="pl-kos">(</span><span class="pl-kos">{</span>
      <span class="pl-c1">baseURL</span>: <span class="pl-s">'http://myurl.com'</span><span class="pl-kos">,</span>
      <span class="pl-c1">withCredentials</span>: <span class="pl-c1">false</span><span class="pl-kos">,</span>
      <span class="pl-c1">loader</span>: <span class="pl-c1">true</span> <span class="pl-c">// Custom property</span>
<span class="pl-kos">}</span><span class="pl-kos">)</span><span class="pl-kos">;</span>

<span class="pl-s1">instance</span><span class="pl-kos">.</span><span class="pl-c1">interceptors</span><span class="pl-kos">.</span><span class="pl-c1">request</span><span class="pl-kos">.</span><span class="pl-en">use</span><span class="pl-kos">(</span>
      <span class="pl-s1">config</span> <span class="pl-c1">=&gt;</span> <span class="pl-kos">{</span>
        <span class="pl-smi">console</span><span class="pl-kos">.</span><span class="pl-en">log</span><span class="pl-kos">(</span><span class="pl-s">'request'</span><span class="pl-kos">,</span> <span class="pl-s1">config</span><span class="pl-kos">)</span><span class="pl-kos">;</span> <span class="pl-c">// Does not show the "loader" property</span>

        <span class="pl-k">if</span> <span class="pl-kos">(</span><span class="pl-s1">config</span><span class="pl-kos">.</span><span class="pl-c1">loader</span><span class="pl-kos">)</span> <span class="pl-kos">{</span>
          <span class="pl-en">showLoader</span><span class="pl-kos">(</span><span class="pl-kos">)</span><span class="pl-kos">;</span>
        <span class="pl-kos">}</span>

        <span class="pl-k">return</span> <span class="pl-s1">config</span><span class="pl-kos">;</span>
      <span class="pl-kos">}</span>
<span class="pl-kos">)</span><span class="pl-kos">;</span></pre></div>
<h4 dir="auto">Expected behavior</h4>
<p dir="auto">It should be available for further use on the interceptors, because the same code is working on version 0.18.1.</p>
<h4 dir="auto">Environment</h4>
<ul dir="auto">
<li>Axios Version: 0.19.1 and 0.19.2</li>
</ul>
<h4 dir="auto">Additional context/Screenshots</h4>
<p dir="auto">Please let me know if I'm doing this wrong, and there's a new way to do.</p>
<p dir="auto"><strong>Describe the bug</strong><br>
Custom settings are not persisted to each request</p>
<p dir="auto"><strong>To Reproduce</strong></p>
<div class="highlight highlight-source-js notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="
var axios = require('axios')
var axios2 = axios.create({retry: true});
// should log &quot;Retry is true&quot;
axios2.interceptors.request.use(request =&gt; console.log('Retry is ' + request.retry));
axios2.get('http://www.blankwebsite.com/');
"><pre class="notranslate"><span class="pl-k">var</span> <span class="pl-s1">axios</span> <span class="pl-c1">=</span> <span class="pl-en">require</span><span class="pl-kos">(</span><span class="pl-s">'axios'</span><span class="pl-kos">)</span>
<span class="pl-k">var</span> <span class="pl-s1">axios2</span> <span class="pl-c1">=</span> <span class="pl-s1">axios</span><span class="pl-kos">.</span><span class="pl-en">create</span><span class="pl-kos">(</span><span class="pl-kos">{</span><span class="pl-c1">retry</span>: <span class="pl-c1">true</span><span class="pl-kos">}</span><span class="pl-kos">)</span><span class="pl-kos">;</span>
<span class="pl-c">// should log "Retry is true"</span>
<span class="pl-s1">axios2</span><span class="pl-kos">.</span><span class="pl-c1">interceptors</span><span class="pl-kos">.</span><span class="pl-c1">request</span><span class="pl-kos">.</span><span class="pl-en">use</span><span class="pl-kos">(</span><span class="pl-s1">request</span> <span class="pl-c1">=&gt;</span> <span class="pl-smi">console</span><span class="pl-kos">.</span><span class="pl-en">log</span><span class="pl-kos">(</span><span class="pl-s">'Retry is '</span> <span class="pl-c1">+</span> <span class="pl-s1">request</span><span class="pl-kos">.</span><span class="pl-c1">retry</span><span class="pl-kos">)</span><span class="pl-kos">)</span><span class="pl-kos">;</span>
<span class="pl-s1">axios2</span><span class="pl-kos">.</span><span class="pl-en">get</span><span class="pl-kos">(</span><span class="pl-s">'http://www.blankwebsite.com/'</span><span class="pl-kos">)</span><span class="pl-kos">;</span></pre></div>
<p dir="auto"><strong>Expected behavior</strong><br>
Custom default parameters should be persisted to each request.</p>
<p dir="auto"><strong>Environment:</strong></p>
<ul dir="auto">
<li>Axios Version [hash <a class="commit-link" data-hovercard-type="commit" data-hovercard-url="https://github.com/axios/axios/commit/a17c70cb5ae4acd7aa307b7f7dc869953dea22c4/hovercard" href="https://github.com/axios/axios/commit/a17c70cb5ae4acd7aa307b7f7dc869953dea22c4"><tt>a17c70c</tt></a>]</li>
</ul>