I found the setCookieInNewWindow in the file OptOutManager.php, but any manual change there (0 instead of 1) doesn’t help.
Also, on my tablet my browser freezes when I visit a site with popup for Piwik setting. In the past hours I got the idea that this topic could even get into bug area for Piwik :). I mean in general _blank is not really the future, and in addition the mobile browser don’t support the popup solution. As this is all in all a real privacy matter, Piwik should think about it.
So here again: Is there any setup to get the popup (or not) for the Piwik setting in the iframe?