post processing stack is now built in but does not automatically replace old script?

I have no idea what happened but it seems like post processing stack support no longer needs to be imported, but things were working fine until i upgraded to Unity 2019.2?

Now i have to replace all cinemachine post processing components in my game cause it doesn't replace the component automatically :/

i assume upgrading from 2018.3 to 2019.2 caused this problem, it's just really unfortunate is gonna take a lot of time to fix :/