[runtimes][monogame] rendering order with clipping mask causing rendering issues

[NebulaSleuth]

We have an animation that uses a clipping mask. This animation was rendering correctly until we upgraded to the 4.2 Monogame runtime.

What happens is that a specific attachment/element stops rendering when the clipping mask ends its keyframe sequence (stops moving). In the included example, the 'Santa Hat' disappears when the eyes finish blinking (masking of the eyes finishes)

This was working in 4.1.x. We also notice that by changing the draw order to place the Santa Hat before the clipping mask, then the issue does not occur.

The Spine application shows correctly, as does the SkeletonViewer.jar. But renders incorrectly using Monogame.

I have included a link to download a zip including project files, exported files and a video showing what happens (sorry for the poor framerate on the screen capture)

spinebug.zip