Bad navigation UX

Playing games on 9o3o is inconvenient because:
- The Play button is not actually a link to the game page, so you can't open it in a new tab or see where it goes when hovering.
- Once you're on the game page, getting back to the Browse page is slow because even if you click the browser's Back button, the entire page reloads. (On other sites, clicking the Back button is very fast because the browser can use its cache.) Also, when the Browse page reloads, it does it by navigating to a new URL, thus making the browser's Forward button not work to reopen the game.

I think it would be better if the game opened in a sort of "theater mode overlay" on top of the Browse page, instead of opening a whole new URL. There would be an X button to close the game and continue browsing. This would improve the user experience a lot.

Another possibility would be to make the Play button a proper link, and make it open in a new tab by default.

Start by locating the Play button and the Browse and game-page navigation entry points. Compare the proposed theater-mode overlay with making Play a proper link, then define one approach whose completed behavior preserves efficient back navigation and provides a way to close the game and continue browsing.

Written by the indexing model from the issue text.