I rather fix over-extrusion in the firmware (fixing ESteps per mm) than in the slicer software.
Anyway if you need to update it when changing filament type, it might be better to use the
"Filament packing density" setting (in the "Dimension" module/tab).
For instance I recently tried Laywoo(d) and the hobbed bolt seems to bite much more deeper in that than in regular PLA.
Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.