display:grid in Thunderbird

Before

<div style="display: grid;
            grid-template-columns: 1fr 1fr; gap: 16px;">
  <div>Item 1</div>
  <div>Item 2</div>
</div>

After

<table role="presentation" width="100%" cellpadding="0"
  cellspacing="0" border="0">
  <tr>
    <td width="50%" style="padding: 8px;" valign="top">
      Item 1
    </td>
    <td width="50%" style="padding: 8px;" valign="top">
      Item 2
    </td>
  </tr>
</table>