The last-minute hangout is the surprise star of our postpandemic social lives, helping to re-energize our friendships. Over the past few years, many gatherings had to be meticulously arranged in advance—and often got canceled anyway because of Covid-19 concerns. And recently, a season of swirling flu, RSV and other viruses, a ramped-schedule of postpandemic events, as well as recurring bouts of social burnout have continued to disrupt long-range plans.

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