You could not make it possible for administrators to choose whether custom fields in the sidebar of the messages you need to display text or an icon?
If such contact skype or web site link, instead of show you could not give the possibility to show an icon?
It might come in handy for many custom fields.
There is a Plugin for WCF2 which gives you some icons to choose.
No idea if it will still work in WCF2.1.
Dont know the Forum where you can get it by Heart, its not in the Woltlab Filebase.
I know the plugin. But it would be nice to have something already built on wbb 4.1 right?