Bards get Expertise at level 3. How does this work?
For example, if I have a standard proficiency bonus of +2, and if I have proficiency in Perception with a Wisdom ability modifier of +2, then my Perception is +4. If I choose expertise in Perception, does it double the +4 to Perception +8, or does it double the proficiency bonus only to +4 for a total of Perception +6?