Trying to see Super Game Boy border in Tetris DX, it seems that this is a little messy, basically it will not work in sgb and sgb2, but works where shouldn't:
Game Boy Color (game goes to black and white?):
Super Game Boy:
Super Game Boy 2 and GBA (border are gray before, blue in other screen, and then in the game it is red):
PS: using "Display Super Game Boy borders", vba-m 1229 in linux.