Indeed, this helps, thanks! Also there's a switch between car and public transport.
The thing remains weird nevertheless. I'd assume that if you click a point at this mode, the point stays put, because the time from this point to this point remains zero and does not change. But the map twitches so that the point under cursor / tap moves away. I suspect that the map shows some other kind of approximation, not the time to the point clicked. Likely the grid that defines effective times is somehow sparse, and approximating the distortion well when a click hits rather away from a node is hard. But that would still be weird, because I suppose that points like airports and train terminals should definitely be major nodes of that grid.
The thing remains weird nevertheless. I'd assume that if you click a point at this mode, the point stays put, because the time from this point to this point remains zero and does not change. But the map twitches so that the point under cursor / tap moves away. I suspect that the map shows some other kind of approximation, not the time to the point clicked. Likely the grid that defines effective times is somehow sparse, and approximating the distortion well when a click hits rather away from a node is hard. But that would still be weird, because I suppose that points like airports and train terminals should definitely be major nodes of that grid.