It’s been a year of sacrifice, social distancing and skyrocketing stress. Can we at least enjoy holidays? In terms of risk, the timing of the holiday season couldn’t be worse. The coronavirus is raging across the country, setting new daily infection records. More than 300,000 Americans have died of Covid-19, and small gatherings are believed to be fueling much of the spread. While public health officials caution against family and friends gathering in each other’s homes, they know many people plan to spend the holiday together anyway. The solution? A scaled-back holiday celebration — with open windows, fewer people and...