I recently updated Firefox & apparently it breaks my application partially. It works fine on Chrome & previous version of FF.
Firebug is disabled.
Also the problem seems to occurs on fairly complex window. I have a window with border layout, tree on left, chart on top, & grids on the center inside card layout.
Other simpler windows seems to works fine.
Another weird thing is, if Firebug is enabled, then then problem seems to go away.

Does anyone having similar problem on FF 18?
ExtJS version used: ext-4.1.1