The map window is as wide as your screen
The game used to draw into 512×480 and no further: sixteen tiles by fifteen. The old zoom did not help — it thinned out the pixels of an already drawn scene, so the picture blurred and the frame stalled. Now the magnifier grows the window itself: the game renders into its own frame the size of the browser window, one to one, and the map area goes from 16×15 tiles to something like 45×27. The panel moves to the right edge, the minimap draws the bigger viewport rectangle, the cursor and the edge scrolling work at the real edges of the screen, and the aspect ratio is kept. The page always opens at the native size — only the magnifier buttons change it.