ID 372904 - Setting up a custom " QT_PLUGIN_PATH " Environment variable does not append within Nuke on launch

The plugin path setup should be changed to add the new path, instead of setting the path, which removes already provided variables. 

Customer reported version
11.2__11.2v4
 

Customer reported platform
Linux CentOS7

Steps to reproduce

1) Add your custom QT plugin to the QT_PLUGIN_PATH Environment Variable

    Further information can be found here: http://doc.qt.io/qt-5/deployment-plugins.html

2) Open Nuke, and call your plugin within the Script Editor
 

Result: The custom plugin will not be found, Nuke will throw an exception

Workaround

To setup custom Qt Libraries, users need to call the following on launch within their init.py location:

from PySide2 import QtCoreQtCore.QCoreApplication.addLibraryPath("path/to/custom/library")

Reproduced by support

This bug has been reproduced in:
Nuke11.2v4 - Windows 7 - Mac10.13 - CentOS6.9
Nuke11.2v1 - Windows 7
Nuke11.1v4 - Windows 7

Nuke11.1v1 - Windows 7
Nuke11.0v4 - Windows 7
Nuke11.0v1 - Windows 7
Nuke10.5v7 - Windows 7 - Mac10.13 - CentOS6.9
Nuke10.5v1 - Windows 7
Nuke10.0v6 - Windows 7
Nuke10.0v1 - Windows 7
Nuke9.0v9 - Windows 7
Nuke9.0v1 - Windows 7
Nuke8.0v7 - Windows 7
Nuke7.0v10 - Windows 7 - Mac10.13 - CentOS6.9'

Earliest version tested
- This issue appears to be in all versions of the product

Expected behaviour
Users can setup custom Qt libraries on launch, without setup scripts.

Actual behaviour
Importing of custom Qt libraries do not occur and cause exceptions, unless the user adds it  through Python calls on launch.