title: thead not showing in HTML email
body: <p>I'm coding my own HTML email using a Mailchimp template. I have a thead for 2 tables and they look fine in a webpage, but they are not rendering in Mailchimp or in any test email platforms (Gmail, Apple Mail, Outlook 365 etc). It simply just omits the entire thead block. Why is my thead not showing up?</p>
  
  <pre><code>&lt;table border="0" cellspacing="0" class="mcnTextContentContainer" 
  width="100%" style="min-width: 100% !important;background-color: 
  #FFFFFF;"&gt;                                                               
      &lt;thead&gt;
         &lt;tr&gt;                                                   
         &lt;th bgcolor="#f2f2f2" valign="top" class="mcnTextContent" 
            style="padding: 18px;color: #F2F2F2;font-family: Poppins, 
            Arial, sans-serif;font-size: 14px;font-weight: normal;text-
            align: center;"&gt;
  
           &lt;span style="font-size:18px; color:#000000; text-
            align:center;"&gt;&lt;strong&gt;Shipping Information&lt;/strong&gt;&lt;/span&gt;
  
          &lt;/th&gt;
          &lt;/tr&gt;                                                                
      &lt;/thead&gt;
  
      &lt;tbody&gt;
      &lt;/tbody&gt;
  &lt;/table&gt;                                                                  
  </code></pre>