Metallica performs at BottleRock Napa Valley at the Napa Valley Expo on May 27, 2022. Sean Liming/STAFF. NAPA — Taking an informal poll of the 40,000-some attending the opening day of BottleRock Napa Valley on Friday, it was pretty clear who most were there to see. Heavy metal heroes Metallica…

JoJo performs at the Warfield in San Francisco on March 1, 2022. Onome Uyovbievbo/STAFF. SAN FRANCISCO — JoJo just might be one of the more under-appreciated vocalists around. Perhaps her Grammy win in 2020 (with PJ Morton) for Best R&B song has gotten more people to notice, but even…