ID 286604 - Merge2 operations including Stencil and Mask are not being applied to all channels despite being set correctly within the nodes parameters

Problem summary
Merge2 operations; Stencil and Mask,  not being applied to all channels despite being set correctly

Customer reported version
nuke.10.0v5

Customer reported platform
centos6

Steps to reproduce

1) Launch Nuke

2) Open the attached script

3) On the left side is the "new" Merge node (aka Merge2) and on the right is the original Merge.

4) Set the operation to Mask or Stencil in both nodes, and then the "also merge" parameter to "all"

5) Change your view port viewer from RGBA to Test and toggle your display between the two Merge nodes.

RESULT

The old Merge node will correctly generate the stencil or mask where as the "new" Merge2 will not.

Workaround
Use the old Merge node by navigating to the plugins panel and selecting "update plugins" and then use the old Merge node located in the Other Tab->All Plugins->M

Reproduced by support
Nuke 10.5v5 - CentOS 6.9 - Windows 7 - MacOS 10.12.5
Nuke 10.5v1 - CentOS 6.9 - Windows 7 - MacOS 10.12.5
Nuke 10.0v1 - CentOS 6.9 - Windows 7 - MacOS 10.12.5
Nuke 9.0v9 - CentOS 6.9 - Windows 7 - MacOS 10.12.5
Nuke 9.0v1 - CentOS 6.9 - Windows 7 - MacOS 10.12.5
Nuke 8.0v1 - CentOS 6.9 - Windows 7 - MacOS 10.12.5

Earliest version tested
Checking similarly logged bugs this issue seems to go as far back as Nuke 5.1v6

Expected behaviour
User should view the Stencil/Mask Operation in the user created Test channel using the newer Merge node.

Actual behaviour
The Merge2 node does not accurately display the information within the Stencil/Mask Operation across all channels.