Hi Neil,

Thank you for your question,

The following documentation confirming what is support when formatting messageML tables in Symphony (https://docs.developers.symphony.com/building-bots-on-symphony/messages/overview-of-messageml/messageml-basic-format-tags/tables).

There are many similariates with Symphony messageML to other markup languages such as HTML. However, not all aspects of the markup languages like HTML will be compatible with Symphony messageML.

We would recommend using the Symphony PresentationML Renderer Tool as a way to validate the messageML you are formatting: https://renderer-tool.app.symphony.com/

If you wanted to format & alter the column width of a table using messageML - you can use either the 'pixel' count or the '%'.

Here are two examples showcasing the using the 'pixel' count & '%' tables in messageML:

<messageML>
<table style="width:900px">
    <tr>
        <th style="width:300px">
           column 1
        </th>
        <th style="width:400px">
           column 2
        </th>
        <th style="width:200px">
           column 3
        </th>
    </tr>
    <tr>
        <td style="width:300px">
           value 1
        </td>
        <td style="width:400px">
           value 2
        </td>
        <td style="width:200px">
           value 3
        </td>
    </tr>
</table>
</messageML>

<messageML>
<table style="width: 100%">
    <tr>
        <th style="width: 10%">
           column 1
        </th>
        <th style="width: 20%">
           column 2
        </th>
        <th style="width: 70%">
           column 3
        </th>
    </tr>
    <tr>
        <td style="width: 10%">
           value 1
        </td>
        <td style="width: 20%">
           value 2
        </td>
        <td style="width: 70%">
           value 3
        </td>
    </tr>
</table>
</messageML>