Different height at JComboBox editor and renderer

I have a combo box which uses a custom ListCellRenderer which basically
displays two lines of text (the preferred name of an object and an
alternate name of the object). That works well. The problem is that the
editor for the combobox (which is editable) is being displayed with the
same height as the ListCellRenderer (ie two lines) but I would like it
to be normal and be a single text line height. I can't figure out how
to do this. Is this possible? If so could you please provide an example
of how it is done?

Thanks

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