When I make a comment on a post, there's a checkbox next to the submit button labelled "No bump". What is this for? Surely posts can't be bumped anyway, by comments or other means?

Ditto on the curiosity.

I assume it means the comment won't be listed in the recent comments listing here: https://e621.net/comments?group_by=post

crocogator said:
I assume it means the comment won't be listed in the recent comments listing here: https://e621.net/comments?group_by=post

Just tested with a comment here, looks like you're right.