I’ve been doing this for years and it works great.
The inherent problem with this oft used coaster replacement is that as the condensation forms on the outside of your glass, it eventually follows the laws of gravity and inevitably, the napkin ends up stuck to the bottom of your glass as you are toasting to your friends.
Solution: As soon as your drink is served, lift your drink off of the napkin and grab the nearest salt shaker. Sprinkle the napkin lightly with salt (roughly 3-4 shakes per average salt shaker) and replace your beverage back on your napkin. No more sticky napkin even as it gets saturated from