I have a system based on tree objects, when I press right click on the treeitem appears a menu dynamically, but in firefox 4.x and up, in windows, linux fedora and linux ubuntu occurs a problem, all Events lost control. The problem exists when I do that: I am working in system with no problems, but when I change focus from firefox to other application then return to firefox with right click on treeitem, the problem occurs. There is a video of this problem in the URL http://www.youtube.com/watch?hl=es-419&v=N8e93QnVaj0, I try to solve updating web.js.zk.ext.jquery.js by last release but zk does not work, so I try blocking all events when explorer lost focus and unblocking 100 miliseconds after firefox get the focus, the system works. The problem occurs on client so the event no arrives to server. Thanks a lot.