stamping a turtle shows the turtle on the pen layer, but pasting it does nothing.
That's because pasting is putting the current costume onto a different costume. The turtle costume isn't really a costume, so it shouldn't be able to paste. Stamping onto the stage just stamps the sprite image (not just costume, because it follows graphic effects) onto the pen layer.
is that intentional? why?
i don't think there's any use in not being able to paste a turtle or graphic effects
(arguing that it isn't a bug only really changes it to a feature suggestion)
I like how paste ignores graphic effects. It can make some pretty cool effects, such as, a sprite that can only be seen when over another sprite, basically just a sprite that has a color effect, but when over another sprite, it doesn't have the effect.
instead of a sprite with no costume ending up as an invisible sprite, the turtle is used to indicate that the sprite has no costume.
you could just disable the effects, paste, then enable it again each time (use a warp if you need to)
it also shows the pen color
And things like the size and direction also
turtle is null
the turtle isnt even a costume
its just the morphic.js pen morph