According to Wikimedia Design Style Guide, Foundation's choice of open source serif typeface is Charter.
More info on charter
Web font -
To experiment with the new open typeface, we would like to use Charter as body typeface for print styles.
Though charter has a wide support for many scripts, we should be cautious and use it only for latin scripts to begin with. we can extend the support later
- Deliver web font for printing
- Only body:en should get charter typeface