The default theme in gregarius does not validate. You can see the results at http://tinyurl.com/djxj7 The problem is the -moz-border-radius statements which are gecko specific. The rounded buttons on mozilla are nice, however if gregarius wants to claim that it is (tentatively?) standards compliant I think they should be removed. Anyway, once css3 is mature I think these proprietary extensions will be removed from mozilla. Anyway, if you guys decide not to remove it this is an example of what happenned to my gregarius installation main page. http://test.dcostanet.net/rss/tidy1.html (using firefox 1.0.6 on linux) http://test.dcostanet.net/main_top.jpg http://test.dcostanet.net/main_bottom.jpg I have a similar problem with firefox 1.0.6 on the tiger however it is not as bad. This gets fixed if I remove .frame from look.css in line 265 /* bad bad bad */ .frame,.item,h3.collapsed,table,div.content img { -moz-border-radius: 5px } Sameer Ps. The /* bad bad bad */ is actually in the code :)