CanvasGroup alpha? Trying to upgrade from 2018.1.9 to 2018.3.7

Hi, was the behaviour changed between 2018.1.9 and 2018.3.7? Or is this a bug?
Subcanvases don't follow the alpha of the parent CanvasGroup anymore?

Assume a simple set up like this:
> Canvas (1) + CanvasGroup
|--> Image (1)
|--> Canvas (2) <-- this is a sub canvas
--|--> Image (2)

In 2018.1.9
Image (1) and Image (2) both fades out as CanvasGroup alpha is tweened to 0.
In 2018.3.7
Only Image (1) fades out as the alpha is tweened to 0.
Image (2) does not fade, but is invisible when alpha = 0, and visible when alpha > 0.

 

There are some bugs with images and alpha. Try deleting and adding a new image or work with rawimage

 

I just realised the indentation wasn't working properly, leading whitespace was getting trimmed.
I edited with GIFs instead

 

I didn't think to check the Issues tracker until now.
Looks like its a bug
https://issuetracker.unity3d.com/is...-changing-alpha-parameter-in-the-canvas-group