# Why does Mathematica Spawn Additional Dock Icons on OS X?

I've been running a calculation in parallel that requires a rasterize, and doing this requires one to wrap the rasterization with a UsingFrontEnd command (as is described here). When I do this, my dock is populated by a number of Mathematica icons equal to the number of parallel kernels I use, and then auto-hides them, dimming the icons, but not removing them from the dock:

Does Mathematica do this whenever UsingFrontEnd is used within a parallel routine? I also recall some other instances where this occurs within a Parallel call where I haven't explicitly called UsingFrontEnd, so I'm presuming that this occurs even for implicit launches of the front end.

It's quite annoying to pollute the dock with 8 (or more) icons, so it's something I'd to avoid if possible. But my question is more why does Mathematica behave in this way? I should also mention that the icons remain in the dock even after the parallel operation has completed.

• @Guillochon Theoretically you could look at Links[], see which one looks like the one belonging to the front end, and then manually LinkClose[] it. I just tried this. – Szabolcs Jan 14 '15 at 14:59