Active vs non active buttons in horizontal navbar

I would like to add the horizontal buttons which are displayed in this Foswiki installation into my own WebTopBar, just like this:

I've tried to use the settings from PatternSkin horizontal navigation example, and it somehow works, except for the color of the "inactive" buttons. All buttons give the impression to be active (blue).

The difference between the example and my live situations, is that I am pointing to topics within the same web, and not to different webs.

What do I need to do to make the navbar "feel" which topic is active and which are not?

See: http://wiki.boossy.be ("unset" the navbar again on 14/05/2019, I'll enable it again upon simple request)