Revoking comment's upvote not properly confirmed

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Upvote given to a comment can be undone by clicking on the same arrow used to vote for it, but the displayed number of votes is unchanged until page is refreshed. This is misleading because users would usually think undoing upvote failed although software actually responds to every click on comment vote arrow - if pressed odd number of times vote changes to its opposite, if even it remains as it was - just isn't shown in real time.