I feel like I encountered this before, but can't remember what the issue or solution was and nothing is coming up in search (I'm sure the word I'm looking for to describe it is escaping me).
Take a look:
You can see a starling TextField with a border showing an embedded font (via Animate) and set using a TextFormat. How can I eliminate the space above the numbers that push the text down?
"Kerning" came to mind, but I believe that's the space between characters, whereas this seems to have white space above the font.