ID 389044 - The embedded layout fails to expand when dragging the menu handles to expand the window.

Problem summary:
The embedded layout fails to expand when dragging the menu handles to expand the window.

Customer reported version:
nuke.11.3v3

Customer reported platform:

n/a

Steps to reproduce:

1) Place the attached custom_ui.gizmo and custom_ui.py in the .nuke directory.

2) Launch Nuke and press Tab and type "Update [All plugins]", then press Enter. 

3) Press Tab and type "custom_ui" and press Enter. (clear the error popup)

4) Copy/Paste this node into the script:

Group {
 addUserKnob {20 User}
 addUserKnob {52 custom_knob l "" +STARTLINE T CustomUI() +STARTLINE}
}
 Input {
  inputs 0
  name Input1
  xpos 0
 }
 Output {
  name Output1
  xpos 0
  ypos 300
 }
end_group

5) Attempt to expand the layout/window and observe the embedded box.

Expected behavior:
The embedded layout should extend to the bottom of the window when expanding the box.

Actual behavior:
The embedded layout will fail to expand with the windows when stretching/growing the box.

Workaround:
Turning the Group into a Gizmo seems to correct the behavior.

Gizmo {
 addUserKnob {20 User}
 addUserKnob {52 custom_knob l "" +STARTLINE T CustomUI() +STARTLINE}
}
 Input {
  inputs 0
  name Input1
  xpos 0
 }
 Output {
  name Output1
  xpos 0
  ypos 300
 }
end_group

Reproduced by Support in:
Nuke 11.3v3 - Windows 10, CentOS 7, macOS 10.13.6

Nuke 11.3v1 - Windows 10

Nuke 11.2v5 - Windows 10

Nuke 11.2v1 - Windows 10, CentOS 7, macOS 10.13.6 - regression

Unable to reproduce bug in:
Nuke 11.1v6 - Windows 10, CentOS 7

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