ID 146858 - Various panels/tabs disappear when closing/opening a project in the same session.

Problem summary
Various panels/tabs disappear when closing/opening a project in the same session.

Customer reported version
nuke.12.1v2

Customer reported platform

win10

Steps to reproduce

1) In Nuke Studio, load the attached custom workspace.

2) Load any Project.

3) Close the current or open another project and view the panels available.

Expected behavior
The opened panels should remain in place and not change or disappear.

Actual behavior
The Sequence/Viewer panels are closed when opening a Project or closing the current one.

Workaround
Resetting the Workspace allows the closed tabs to reappear from their initial state. 

Reproduced by Support in
Nuke Studio/Hiero 12.1v3 - Windows 10

Nuke Studio/Hiero 12.1v1 - Windows 10

Nuke Studio/Hiero 12.0v1 - Windows 10

Nuke Studio/Hiero 11.0v1 - Windows 10

Nuke Studio/Hiero 10.0v1 - Windows 10

Nuke Studio/Hiero   9.0v1 - Windows 10

Nuke Studio/Hiero   1.9v1 - Windows 10

Earliest version tested
Nuke Studio/Hiero 1.9v1 - This issue appears to be in all versions of the product