For Sencha 2.1.

Settings itemHeight to 0 in list causing Browser / Tab to hang and memory of the that Browser/ Tab growing steady and fast.

Simple example:

Code:
/*global Ext:false */
Ext.application({
    launch:function () {
        Ext.create('Ext.List', {
            fullscreen:true,
            itemTpl:'{title}',
                        itemHeight:0,
            data:[
                { title:'Item 1' },
                { title:'Item 2' },
                { title:'Item 3' },
                { title:'Item 4' }
            ]
        });
    } // launch
}); // application()
After executing this piece of code you will get unresponsive Browser or Tab.
Tested on Chrome under Windows 7. Memory will keep growing fast as long as hanging process running.

Expected behavior: Tab should not hang, List should contain all items with height 0.