Adding a header.xml breaks minimize/maximize during match view?

[Reventon]

First of all I'm really new to skinning for FM so I apologize if this is something obvious but I tried searching for it and couldn't find a previous thread.

Even when adding an unmodified header.xml (taken from skins/fm/panels) to the base16_alt skin the result looks like this:

and I have no idea why that is since I believed it was the exact same header.xml it was using anyways.