How to convert html table without <thead> tag?

Question

I am working with flexmark-java for converting HTML to Markdown and am facing a problem with tables. my HTML tables don't explicitly contain tags. I want the converter to automatically recognize the first row as the header. Below is a sample of the HTML table structure I'm working with:

<table>
  <tr>
    <td>Team</td>
    <td>Overview</td>
    <td>Estimated Time</td>
  </tr>
  <tr>
    <td>Arthur</td>
    <td>Needs support for configuring upload recommendation image</td>
    <td>Waiting</td>
  </tr>
</table>

Here's the output markdown:

|--------|---------|----------------|
| Team   | Overview| Estimated Time |
| Arthur | Needs support for configuring upload recommendation image |Waiting|

because there's no thead declared in the html content,so flexmark put the separator line to the first line.

is there any configuration that can make the Markdown format correct?