PathEffectRenderer doesn't call close_group?

I am in the process of developing a custom Renderer for matplotlib. This task relies on the use of open_group and close_group functions. During testing, I noticed an inconsistency in the number of calls to these two functions while working on the example of Contouring the solution space of optimizations. This issue seems to be linked to the use of patheffects. After some investigation, it appears that in Collection.draw, if any path effects are present, the renderer is updated to PathEffectRenderer. Subsequently, close_group is called on this updated renderer, but this call does not reach the original renderer. I am uncertain if this is the intended behavior or a bug.

This was reported as

and should be fixed by