This only works for non-zero karma.
The source code of the pages contains hypothetical % positive for the cases when a comment gets upvoted or downvoted by 1 point, so sufficient information about comments with zero karma is always present as well.
And because you can retract votes, you can always upvote or downvote temporarily to move it off of 0.
The source code of the pages contains hypothetical % positive for the cases when a comment gets upvoted or downvoted by 1 point, so sufficient information about comments with zero karma is always present as well.
And because you can retract votes, you can always upvote or downvote temporarily to move it off of 0.