When Alpha Filter is used in combination with a custom filter it gives incorrect result

[Melwyn]

I have a particular combination of Containers and Sprites in which Alpha Filter and a Custom Filter (Blend filter) are applied on different nodes of the subtree

For this combination I'm getting incorrect result

Container(Alpha Filter)->Container->Sprite(Blend Filter)

JS Fiddle: https://jsfiddle.net/68gnxsmk/31/

Without Alpha Filter:

With Alpha Filter:

[ivan.popelyshev]

Of course , backdrop is wrong, it takes temporary texture from AlphaFilter which is empty, not the actual screen. How exactly do you want AlphaFilter to work here?