Undo move?

I believe this is a lacking feature. If my opponent moves their Queen in a position where I simply eat it and he did not see it... that is not exactly the funnest and glorious situation, the rest of the game becomes more like a chore than anything else since I know  that I will win and it is only a matter of time.

If both players agree for either to undo a move, it should be so.

If you are playing a friend otb you may agree a takeback.

Playing rated games are subject to the rules of chess.

ya new rule is needed!

Nah. It would just mess uo the game. I've sometimes "dropped" pieces in ridiculous squares accidentaly, esp. when playing on a laptop trackpad. I tell the opponent and we start a new game. Or just resign and live with it. :)

Also, if you play on the phone you can activate a "confirm move" option. You move the piece into place but can undo until you hit the "Submit" button. This could be useful in the browser version of the site too, if the function doesn't already exist here...

Can it be enabled on computers?

        Online games on this site have a "submit move" click-on. Live games don't.

playchess.com has a take back option in all their games. I have used it and had others allow me to takeback a few times. It is pretty cool, espcially when you can tell that it was a mouse error.

Takebacks should never be allowed in rated games.

I agree. They should install a "submit move" button on live chess like they have on Online though. That would eliminate mouse slips. :) Just no takebacks!