First this make the wire batch use the same set of drawing that the main gpencil batch uses (as they share the same VBO data, they need to use the same drawings). Then we skip drawing the onion frames by nullifying the indices in the index buffer. A better way would be to skip these strokes or drawing but that can be done later and seems more bug prone. Pull Request: https://projects.blender.org/blender/blender/pulls/129920