Help with error

[markgoldin]

I have a Tabset with DFs and LGs all over the place.
After data is loaded if I click on any tab I am getting the follofing error:

14:56:08.644:WARN:Log:Error:
	''this.formItem' is null or not an object'
	in http://localhost/beltrailway/mainapplication/forms/main.htm
	at line 704
    PickListMenu.hide(_1=>undef, _2=>undef, _3=>undef, _4=>undef)
        "this.invokeSuper(isc.PickListMenu,"hide",_1,_2,_3,_4);if(this.showModal)this.formItem.focusInItem();this.formItem.$19g=null;this.formItem.$19h();delete this.formItem.$19i"
    hideObservation()
    TabSet.$8b(_1=>[ImgTab ID:generalinfo])
    [o]TabBar.buttonDeselected(_8=>[ImgTab ID:generalinfo])
    [o]ImgTab.setSelected(false)
    StatefulCanvas.setSelected(_1=>true)
    Class.invokeSuper(_1=>null, _2=>"setSelected", _3=>undef, _4=>undef, _5=>undef, _6=>undef, _7=>undef, _8=>undef, _9=>undef, _10=>undef)
    Class.Super(_1=>"setSelected", _2=>Obj{length:1}, _3=>undef)
    ** recursed on [o]ImgTab.setSelected

Next tab click will not generate any error. Can you help?

Thanks