Manifold recently added the option to dislike a comment:

Will this feature last a month?

I will look at Manifold at some point on December 15 and resolve this market according to what I see in the UI. If I'm unable to use Manifold on that day for some reason, this will resolve according to what I see the next time I log on in the following days; or, if there is consensus among traders about whether this feature was present on December 15, I'll accept that for resolution.