Class action plaintiffs from Illinois, Pennsylvania, Virginia and Texas ran into venue problems when they sued McDonald’s Corp. in the Southern District of Illinois for allegedly using product packaging that exposed them to “per- and polyfluoroalkyl substances.” These so-called “forever chemicals,” known as PFAS, can “even at low levels,” allegedly cause “devastating health consequences, especially for vulnerable populations like children and pregnant women.”The Illinois plaintiff is Larry Clark. And the others — Joseph …