ceneo.pl serves a desktop site to B2G. Bug 823364 added an UA override for this domain. The override should be removed once the domain serves mobile content to B2G. This bug tracks the evangelism for the site to recognize the B2G UA and the removal of the override at that time.
OK tested on CLI. Working being redirected to the mobile site. → http HEAD http://www.ceneo.pl/ User-Agent:'Mozilla/5.0 (Mobile; rv:18.0) Gecko/18.0 Firefox/18.0' HTTP/1.1 302 Found Cache-Control: private Date: Tue, 09 Jul 2013 19:46:01 GMT Location: http://m.ceneo.pl Transfer-Encoding: chunked X-Frame-Options: SAMEORIGIN p3p: CP="NOI CURa ADMa DEVa TAIa OUR BUS IND UNI COM NAV INT" On the device, we are also redirected to the mobile site. The CSS is not very good, but that is unrelated to the UA override.
ceneo.pl serves a better looking site to iPhone than to FirefoxOS. How far should we push such issues?
Same site served to Opera Mobile, Firefox for Android, Firefox OS, Android browser. I'm not sure it is worth trying to convince them to move all of that to what they serve to iPhone.