-Styles must be improved (full width for smartphones, selectable text for PGN...)
-Tooltip text should fade (even when mouse stay on it, especially for small screens)
-Checkered stage 2: switch button at reserve position.
-If a played disconnect right after opponent sent a move, it might be never received: secure this
+PGN text is not selectable on desktop computer (understand why?!)
+Mode expert: game.js, button on top (with online indicator)