A gem I’ve just found in Ext.ux.statusbar.StatusBar code: every setText() you call, it’s forcing full page reflow. Try this: setStatus : function(o) { var me = this; o = o || {}; // Ext.suspendLayouts(); if (Ext.isString(o)) { o = {text:o}; } if (o.text !== undefined) { me.setText(o.text); } if (o.iconCls !== undefined) { me.setIcon(o.iconCls); } […]