Roblox broke transparent pixel colors

Hi guys.
I wanted to make 2D game, but run into image problem:
image
Upscaled:
image

Previously, I fixed that with changing transparent pixels colors to colors I need, but this not seems to work anymore.


Test alpha colors
image
Same result

Same map but with 1/255 transparency instead of full zero
image
It showed.

Is it roblox bug or ???