-End of game a bit too verbose: should just say "Black win" ... + show PGN
-Styles must be improved (full width for smartphones, selectable text for PGN...)
+Checkered chess: need another FEN element, last non-capturing checkered move (if applicable)
+ + need to stack these indicators for alpha beta search
+MarseilleChess: revise bot and test
+Translations (including About page), refresh rules