Between the link and icon. If it has an arrow next to it, to indicate it goes somewhere, etc. Does not include add-ons (off site icon) if a link. This is for the special case where THIS is the indicator (get it) that there's something the associated text does.
Usually horizontally aligned. Left or right of the text. Yes, reveal items and leaf node icons in the reveal list are this. Others maybe, so go find them.
NEVER just put text down without link styling or an indicator!