It looks like this was already reported in the #helpdesk chat, but I wanted to make a note of it in Spectrum feedback too. When replying to a forum post, using the UNDERLINE markup causes a generic error and you're unable to "publish" your reply. Removing the underline fixes it every time. I'll make a few underlined replies to this thread in case anyone is logging errors so they can trace it. :slightly_smiling_face:)