ID 444111 - Artifacts occur when viewing any Deep nodes after a ScanlineRender if the scene contains semi transparent pixels in front of overlapping samples

Problem summary

Artifacts occur when viewing any Deep nodes after a ScanlineRender if the scene contains semi transparent pixels in front of overlapping samples

Customer reported version
nuke.n/a

Customer reported platform
n_a_mac

Steps to reproduce

1) Open the attached Nuke script

2) Compare the ScanlineRender result to DeepSample, notice the difference:

ScanlineRender 

DeepSample

*The more complex the script, the worse the artifacts get:

Expected behaviour
For the results to be the same when viewing a Deep node after the ScanlineRender node

Actual behaviour
There are artifacts

Workaround
If you use a DeepRecolor node, you can bring the colour values back

Reproduced by support
This bug has been reproduced in:

Nuke 12.2v1 - Windows 10, macOS 10.14, CentOS 7

Nuke 12.1v1 - Windows 10

Nuke 12.0v4 - Windows 10, macOS 10.14, CentOS 7

Unable to reproduce bug in:
Nuke 12.0v3 - Windows 10, macOS 10.14, CentOS 7

Earliest version tested
Nuke 12.0v3 - This issue doesn't appear in this version and has regressed