The reason I'm asking this is because I tested IE only hacks, but XenForo "fixed" them so that they worked with all other browsers. I used several IE 8 hacks, for instance height: 200px\9; This should work for all IE versions only according to multiple sources. I have tested this hack on MyBB and XenForo. While with MyBB this hack worked as it should for IE only, with XenForo it worked for all browsers. After investigating the CSS in firebug I saw that XenForo has fixed this CSS to height: 200px; without the \9. Does that mean that IE hacks are not possible with XenForo? PS: I'm talking about hacks, not browser conditionals.