Unless I missed it, I don't see an option to treat captions as raw HTML in the Export dialog for web gallery creation.
If this feature is missing, I'd like to request it for PM6 and PM+.
Most of my 20,000+ nature images include captions with species names properly formatted in italics via HTML (i.e., <i>Genus species</i> becomes Genus species). Displaying those names in plain text would be unprofessional, so removing the HTML is not an option (nor is displaying this text as "<i>Genus species</i>"). I also use HTML for links and other formatting.
Below is a screenshot of Media Pro's web gallery dialog with this option. I would hope adding this feature would be fairly simple.