This is small, but could be irritating.
Could you possible add a piece of code, that would hide
Mark as spam link, when comment's author and issue's assigner are the same person (user)? I don't think, that someone is going to spam its own issues, so we my assume, that this link is pretty useless in this case (scenario).
I can't count, how many times I nearly clicked
Mark as spam, when I actually wanted to click