Comment 8 for bug 1785958

Hmmm.... legacy canvas doesn't really do layers at all, it just relies on the commutative nature of OR (which doesn't help for printing).

It was drawing objects in the order:

Tracks
PCB objects
Zones
Modules

Since PCB objects are going to be predominantly human-readable stuff, and it seems like the copper should go together, I'd propose changing it to:

Tracks
Zones
PCB objects
Modules

for 5.1. Hopefully it's all gone in 6.0, but I wouldn't want to count on that.