Disable back-forward drop markers?
 

Is there a way to turn off the "drop markers" for the back and forward buttons? Perhaps through a hidden preference?

I hate having those. I mean, I know those buttons can display a menu I don't need those black arrows.

I know you can replace the PNG file (I have been doing that with Jon Hicks' icon set) but I have been looking for a way to do this with a "stock" OW install.