Target is the OmnibusF4pro, not sure if this is intentional. I didn’t see it mentioned in release notes. I can set the alt config to option 2, 3, 4, and if I reboot it shows as persistent in the config setting, but the serial options don’t change (no Serial4 appears in full parameter list or serial port tab) in 4.6.1. I flashed back to 4.5.7 and it works as expected.