We are SOGo administrators and have received multiple user reports regarding newsletters from well-known companies and media outlets where “Read more” buttons or large clickable areas are not clickable in SOGo, while they work as expected in other mail clients such as Roundcube, Thunderbird, and Gmail.

After analysis, this behavior is caused by SOGo sanitizing HTML patterns where an <a> element wraps a block-level <table>. When sanitized, the anchor is removed or neutralized, leaving visually styled buttons (usually <td> elements) without an actual <a href> inside, making them non-clickable.

Technically, the HTML in these newsletters is not ideal, as the button text itself is not wrapped in an anchor. Instead, the layout relies on a parent <a> element wrapping a table. Other mail clients apply heuristic rendering and still make the area clickable. SOGo, correctly prioritizing security and standards, does not.

However, from an operational and user-experience perspective, this leads to a recurring issue:
end users cannot interact with legitimate content from widely used senders, and administrators are repeatedly asked to justify why SOGo behaves differently.

Minimal example (simplified)

<a href="https://example.com&quot;>
<table>
<tr>
<td style="background:#000;color:#fff;padding:10px 20px;">
Read more
</td>
</tr>
</table>
</a>

After sanitization, the <a> is removed or detached, leaving a styled <td> without a clickable link.