Destoyng buildings bug

[maway]

Dont found where bug section is so i will post there.
Destroyng buildings is slow, but if i start upgrading factory from level 1 to level 2 and then press destroy that will be much faster. Its not a big bug, but however it is. check yourself.

[NoQ]

Well, sounds as if this sort of trick costs money, which defeats the purpose anyway.