You can manually export a savegame in the options. Although, it should save automatically. If it doesn't your browser either doesn't support HTML5 localStorage (that would mean it's a very old version), or your browser's security settings are preventing the game from saving to localStorage.
You can manually export a savegame in the options. Although, it should save automatically. If it doesn't your browser either doesn't support HTML5 localStorage (that would mean it's a very old version), or your browser's security settings are preventing the game from saving to localStorage.