[xwiki-users] StyleSheetExtension doesn't work on myxwiki.org ?

Hello, I attached a page with StyleSheetExtension object on http://coc.myxwiki.org/xwiki/bin/view/Sandbox/style but it doesn't work. http://coc.myxwiki.org/xwiki/bin/view/Sandbox/style http://coc.myxwiki.org/xwiki/bin/edit/Sandbox/style?editor=object with simple CSS instructions: p { color:red; } My "admin" user account need PR to use StyleSheetExtension object? Thxs Pascal B