I just released 3.1.1, which adds a dark style option for dark sites for users of v2 comment system, and also fixes a bug. This latter should fix the slowness some people were experiencing.
see here for a demo and for more information.
If you have any issues, post a comment below with the exact issue so other people can “thumbs-up” if they are having the same.
This makes it easier to keep track of issues with the current version, instead of having a mass of comments which may or may not be relevant.