I guess this is primarily for devs:
The title says it all. When pd starts up, it does 2 instances of canvas_new() calls. More interestingly, it does not do canvas_free for those two instances when closing pd, suggesting this is a memory leak. So, what gives? Why does it create 2 invisible canvases, what is their function, and how do they differentiate from the regular canvases.
NB: Not sure if this makes any difference but this is pd-l2ork code based on pd-extended...