ID 509491 - Nuke crashes when viewing a ScanlineRender with an upstream EdgeExtend node

Problem summary
Nuke crashes when viewing a ScanlineRender with an upstream EdgeExtend node.
 
Customer reported version
Nuke 13.1v3
 
Customer reported platform
CentOS 7
 
Steps to reproduce
 
1) Open Nuke 
 
2) Create a CheckerBoard node
 
3) Create a Roto node downstream of the CheckerBoard, and draw a shape in the Viewer. 
 
4) Set the Roto's premultiply knob to alpha.
 
5) Create an EdgeExtend node, downstream from the Roto.
 
6) Create a Card, and connect its input to the EdgeExtend.
 
7) Create a Camera node. Move the Camera in the 3D Viewer, so that the Card can be viewed through it. 
 
8) Create a ScanlineRender node. Connect the obj/scn input to the Card and the cam input to the Camera node.
 
9) Connect the Viewer to the ScanlineRender node and view the 2d output, by pressing the Tab key in the Viewer.
 
Expected behaviour
You should be able to view the output of the ScanlineViewer, without Nuke crashing.
 
Actual behaviour
Nuke crashes when viewing a ScanlineRender with an upstream EdgeExtend node.
 
Workaround
You should be able to work around the issue by connecting the Roto node to the Matte input of the EdgeExtend.