Thread:Project:Support desk/Add tab and open in new window/tab/reply (3)

You may have already discovered this, but $wgExternalLinkTarget is ignored by the Skin code, which is where these links are rendered.

If you are using the Vector skin, you would have to look at the file in skins/Vector.php, and the  method.

You could create your own skin that would, for example, respect $wgExternalLinkTarget by simply overriding the  method.