When I went from 0.95 to 0.96, card switches in my tab panels acquired slide animations. This conflicts with the Ext.TabPanel documentation, which says the default value of the animation config is null, meaning no animation. Moreover, even explicitly setting the animation config to null has no effect. The problem is that Ext.TabBar.onTabTap imposes an explicit animation. It should definitely not do so. If this animation is retained at all, it should be in the defaults for Ext.TabBar and its subclasses.
UPDATE: Sorry, I see this was already reported earlier today: