Sitting at her computer on her living room couch, she tried to check the latest messages on Slack, only to find her account was locked. She then pulled up her work email account, or tried to. Also locked. She logged onto her personal email account and saw something in her inbox from a human resources executive at Twitter. “Your recent behavior has violated company policy,” the email said, according to Ms. Solomon. She turned to her husband and said, as she recalled in a recent interview, “I guess I don’t work here anymore.”