ID 380361 - Running hiero.ui.openInViewer() then disabling an OCIOColorSpace Soft Effect will cause Nuke to crash

Problem summary
Running hiero.ui.openInViewer() then disabling an OCIOColorSpace Soft Effect will cause Nuke to crash.

Customer reported version

Nuke 11.1v4

Customer reported platform
Windows

Steps to reproduce
1) Open Nuke Studio and import an image sequence (File > Import File(s)...) and drag it onto the Timeline to create a new sequence.

2)Apply an OCIOColorSpace soft effect applied to the clip on the Timeline (Right click > Effects > Colorspace).

3) Run the following line of code in the Script Editor:

hiero.ui.openInViewer(hiero.core.BinItem(hiero.core.projects()[0].sequences()[0]))

4) If you now disable the OCIOColorSpace soft effect on your Timeline (select the soft effect and press d on the keyboard), Nuke should crash.

Reproduced by support
This bug has been reproduced in:
Nuke  Studio 11.2v5 - Windows 10 - macOS 10.13 (High Sierra) - Linux CentOS 6
Nuke  Studio 11.1v6 - Windows 10
Nuke  Studio 11.0v4 - Windows 10
Nuke  Studio 10.5v8 - Windows 10
Nuke  Studio 10.0v6 - Windows 10
Nuke  Studio 9.0v9 - Windows 10
Nuke  Studio 9.0v5 - Windows 10 - macOS 10.13 (High Sierra) - Linux CentOS 6 - Regression

Unable to reproduce bug in:
Nuke  Studio 9.0v4 - Windows 10 - macOS 10.13 (High Sierra) - Linux CentOS 6

Unable to test this in Nuke 11.3v1 due to the following bug:

TP 380355 - Running hiero.ui.openInViewer() will cause Nuke Studio to crash immediately

Earliest version tested
Nuke Studio 9.0v4
- This issue no longer appears in this version and has regressed

Expected behaviour

Running hiero.ui.openInViewer() should open the clip in the Viewer and disabling the soft effect should not cause Nuke to crash.

Actual behaviour

Running hiero.ui.openInViewer() then disabling an OCIOColorSpace Soft Effect will cause Nuke to crash.