[paulycy]

There are none in this PDF. Adobe Illustrator probably generates them, I guess.

It turns out that you can see the layers in other programs that work like adobe illustrator, like inkscape, which I've used to see the layers myself.

[cartan]

Now I tried both Inkscape and Foxit. No layers. Note also that the screenshot in post #5 shows only a layer 1, but no layer 2.