Virtual joystick opacity do not work

[joonitto]

1. i did. same issue
2. steps:

1. make a clean project
2. project setting → input → add Default touch interface → run project → move and check joystick’s active/inactive opacity → inactive opacity is ‘0.2’ but it work like ‘1’

3. screen shots

** additional information :
It totally works in Engine ver 4.8.2.