You should probably create an issue on GitHub for it.
For future reference, there are 3 points in time when you can determine whether a link should carry a nofollow
attribute:
- At the time it's posted.
- At the time the page is sent to the client. (server-side)
- After the page has been sent to the client. (client-side)
For search engines, I assume only 1 and 2 matter. The first is efficient, the second is more dynamic. Changing domains could be an issue too.