RE: header-line and mode-line faces

[Drew Adams]

> > They are different faces, and you can also customize them 
> > separately. But header-line inherits from mode-line *today*. Why?
> 
> So that it can share some of its attributes.  E.g. if you change the
> font-family or the size of the mode-line it'll change the 
> corresponding attribute of the header-line as well.

Exactly.

I am suggesting that, by default, it share all of its attributes. That's all.