In that specific part did you saw, in the end, some books going away too? Very good indeed :-)

wow, nearly $7k. Amazing how much a simple but topical game can gather in popularity and funds.

That's nothing for a game like this, taking 6 months.

It's a LOT from a donate button. Donate buttons generate barely any revenue at all, generally speaking. This game must have either got lucky with the crowd that's playing it, or has literally millions of players already.

Oh sure, for donations that's a lot. A good rule of thumb is asking for donations returns 1-10% compared to selling software for a fixed price. So the game perhaps could have brought $70-700k. Highly dependent on the type of software industry though.