[4.1.0 b2] Error in grid via xtype only in IE

[TiloS]

In 4.1.0 b2 the following grid gives an error only with IE 8 and 9:
For the property "isComponent" can't be called a value: The object is null or undefined

In FF, Chrome and Safari there is no error.

Ext.define('bap.view.GridD' , {    
    extend:'Ext.grid.Panel',
    alias:'widget.gridD',
    columns:[
        {
            header:'a'
        }
    ]

{
    id: 'gridD',
    xtype: 'gridD'
}

Debugging shows the error in: Ext.ComponentManager - create

if (component.isComponent) {

Is there a workaround for IE?

[evant]

There's not enough information, however it sounds like you've got an extra comma somewhere.

[TiloS]

After 1 hour search I have found one comma . Sorry and thank you.

But IE is pretty dumb, don't give information where to look. It was not the grid it was a window which is created in afterrender of the grid. How is this to find with debugging!

[evant]

Yeah, it certainly is a pain isn't it.