Assuming you don't use Javascript, kind of. Dillo supports XEmbed, so you can run it embedded in another X windows. This is done by Claws Mail to render emails

Assuming you don't use Javascript, kind of. Dillo supports XEmbed, so you can run it embedded in another X windows. This is done by Claws Mail to render emails as HTML [1]. [1]: https://www.claws-mail.org/plugin.php?plugin=dillo https://www.claws-mail.org/plugin.php?plugin=dillo