[Phanx]

Originally Posted by Rainrider oUF does add a border texture to the aura buttons unless the layout provides its own auras.CreateIcon function.

I'm looking at elements\aura.lua right now, and I see the following objects being created on each aura button:

* cd (cooldown),
* icon (texture),
* count (fontstring),
* overlay (texture), and
* stealable (texture).

None of these appear to be a border. The "overlay" texture is what gets colored by debuff type. Based on the OP's description it is a highlight that covers the whole icon, so if s/he wants it to be a border instead of a highlight, that should be done by changing the texture file and coords, eg:

self.Buffs.PostCreateIcon = function(element, button)
    button.overlay:SetTexture("Interface\\AddOns\\oUF_MyLayout\\BorderTexture")
    button.overlay:SetTexCoord(0, 1, 0, 1)
end

Maybe you're thinking of the "border" that's built into most of Blizzard's actual icon textures? That is part of the icon texture, and cannot be colored separately from the whole icon. You can get rid of it by "clipping" the texture:

self.Buffs.PostCreateIcon = function(element, button)
    button.icon:SetTexCoord(0.07, 0.93, 0.07, 0.93)
end