Pre-fetch map tiles of the next chapter

[fnorf]

Clicking to the next chapter of a map pretty much always leads to the browser loading the map background tiles just in the moment. The user sees either flashes or more-or-less horribly ugly scaled tiles.

Please pre-fetch at least the nearest tiles for the next (or next few) chapters in advance so the transitions are less jarring.

If you don't see the problem, try throttling your internet connection.