Fencer: Swift is a Windows browser based on WebKit, Safari's rendering engine. It is still alpha, but for testing of the rendering it should be ok, I guess.
(hide) Play a game in real time with an online opponent! For this to be possible, you and your opponent have to select the action "Move and stay here" as default and then reload the page with the F5 key! (TeamBundy) (show all tips)