ID 402338 - Adding text to a user knob's text field does not save it first time

Problem summary
Adding text to a user knob's text field does not save it first time. 

However, entering the text into the text field a second time will resolve the issue.

Customer reported version
Nuke 11.3v4

Customer reported platform
centos7

Steps to reproduce

1) Open Nuke and create any node.

2) Right click the node properties and select Manage User Knobs...

3) Click the 'Add' drop-down and select a knob with a text field, such as a Text knob.

4) Give it a name, a label and fill in the Script or Text field with code/text.

5) Click OK.

6) Click Edit to view the code/text and notice that it has not been saved.

Expected behaviour
The text field should be saved first time.

Actual behaviour
The text needs to be entered into the text field a second time for it to be saved.

Workaround
Entering the text into the text field a second time will resolve the issue. However, this is not an ideal solution for users.

Reproduced by support
This bug has been reproduced in:

Nuke 13.0v1 - macOS 10.13 (High Sierra) - Linux CentOS 7

Nuke 11.3v5 - macOS 10.13 (High Sierra) - Linux CentOS 7

Nuke 11.3v1 - macOS 10.13 (High Sierra)

Nuke 11.2v1 - macOS 10.13 (High Sierra) - Linux CentOS 7 - Regression

Unable to reproduce bug in:
Nuke 13.0v1 - Windows 10

Nuke 11.1v6 - macOS 10.13 (High SIerra) - Linux CentOS 7

Earliest version tested
Nuke 11.1v6
- This issue no longer appears in this version and has regressed and macOS and Linux