Shaders + Geometry Masks?

I don’t have any code to show at the moment, so more looking for guidance on the theory.

I’m playing with RexRainbow’s Glow plugin, applying it to the entire scene via the main camera. However, a GameObjects.Graphics object that uses a Phaser.Display.Masks.GeometryMask stopped rendering the mask. The Graphic object still renders, just the mask isn’t applied anymore.

Is this expected / known? Is there some core, fundamental conflict between shaders and Geometry Masks that they don’t work together so the Mask is removed?

For reference, The mask is used to cut out a portion of the graphics using setInvertAlpha