Tabbedcomponent outline

I’m trying to get rid of the white outline around a tabbedcomponent but I can’t seem to manage it. I’ve been through almost every colour setting I can find, and have tried various lookandfeel tricks but I can’t seem to get rid of it? You can see what I mean it in the following screenshot:


What am I missing? Thanks.


I think you need to set this to 0.

Brilliant. I knew it was there somewhere!