Forwarding html email in webmail?

If you forward as a message/rfc822 attachment, it should forward everything. To do that, mark the checkbox next to the message(s) you want to forward, and then use the dropdown menu (or something - it’s been a while) to forward the message(s). There may be another way to do what you want, but that’s probably the easiest. The original message will be attached in its entirety encapsulated in your message.