ID 548197 - RotoPaint brush strokes are not cached in the Viewer until a non brush stroke knob is edited

Problem summary
RotoPaint brush strokes are not cached in the Viewer until a non brush stroke knob is edited
 
Customer reported version
nuke.14.0v5
 
Customer reported platform
Windows 10
 
Steps to reproduce
 
1) Open Nuke

2) Create a Rotopaint node

3) Open the Script Editor and run the following code, it should return True:
 

nuke.activeViewer().node().frameCached(nuke.frame())

 
4) In the RotoPaint node, create a Bezier shape
 
5) Run the code again, it should still return True
 
6) Create a Brush stroke
 
7) Run the code again, the command now returns False, showing that the brush stroke has not been cached
 

 
Expected behaviour
For the RotoPaint brush stroke to be cached
 
Actual behaviour
The RotoPaint brush stroke is not cached, meaning Nuke will have to re-render it after changing frame
 
Workaround
Change the opacity of the stroke to anything else, then back to 1, now the frame has been cached. This seems to work on any knob.
 
Reproduced by support
This bug has been reproduced in:
Nuke 14.0v5 - Windows 10, CentOS 7, macOS Monterey
Nuke 10.0v1 - Windows 10
 
Earliest version tested
Nuke 10.0v1 - This issue appears to be in all tested versions of the product