Welcome to Critical Mass, Law.com’s weekly briefing for class action and mass tort attorneys. I’m Ellen Bardash, filling in for Amanda Bronstad this week. 3M has headed back to trial in Florida for its third fight over allegedly defective earplugs said to have left military veterans with hearing issues. The 11th U.S. Circuit Court of Appeals has upheld the bulk of Equifax’s data breach settlement. Both sides are lawyering up in litigation over electricity and gas companies’ actions during Texas’ winter storms.