@pydsigner probably at some point the highlight quoter was modified to restrict its selection to the post's main content element. The raw element is outside of that, so it's seeing nothing and quoting the whole post.
@boomzilla yes, the view raw script was something I'd written in my userscript. I'd originally made it a button next to "reply", but people complained that it broke their "click first blue button to reply" workflow so it was moved under the menu instead. Also the reply as topic option was from my userscript, and shared some of the same code (it also has to fetch the raw post to quote it).