Latest Facebook Messenger Lite 267 user agents:

User Agent Platform Device
Mozilla/5.0 (iPhone; CPU iPhone OS 13_4_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML like Gecko) Mobile/15E148 LightSpeed [FBAN/MessengerLiteForiOS;FBAV/267.0.0.57.120;FBBV/218062475;FBDV/iPhone12 3; iOS 13 iPhone 12
Mozilla/5.0 (iPhone; CPU iPhone OS 13_3 like Mac OS X) AppleWebKit/605.1.15 (KHTML like Gecko) Mobile/15E148 LightSpeed [FBAN/MessengerLiteForiOS;FBAV/267.1.0.63.120;FBBV/218223117;FBDV/iPhone12 1;FB iOS 13 iPhone 12