paintListBoxItem rowNumber out of range

I’m trying to use a ListBox so i’ve made a custom ListBoxModel, but the ListBox is providing rowNumbers that are too high. The docs make a mention that this may happen, my question is why/when does it happen, and what am i supposed to do with it. I’m having a ListBox with a model containing 5 items and the listbox is sized to be exactly 5 rows high so this extra callback seems quite odd to me and i have no idea what to do with it, do i just discard it? or how can i prevent it from happening?