Two NodeComboBox added to a BaseNode will not draw correctly

[claudio-alvaro-wbgames]

Create a BaseNode with two comboBoxes (using add_combo_menu) with enough items for the first's listView to overlap the second (at least 5 elements). Note how the second comboBox draws over the open listView of the first comboBox.

I believe the issue here is that each widget is bundled into a separate QGraphicsProxyWidget container, thus drawn independently (no consideration for the state(s) of the other widgets).

[jchanvfx]

Hi @claudio-alvaro-wbgames,

Thanks catching the bug I think this might be related to this issue #414