Latest Facebook Messenger 215 user agents:

User Agent Platform Device
Mozilla/5.0 (Linux; Android 10; CPH1931 Build/QKQ1.200209.002; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/81.0.4044.138 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/215.0.0.19.101;] Android 10 A5 (2020)
Messenger [FBAN/MessengerDesktop;FBAV/215.0.0.10.211;FBDV/iMac21,1;FBSN/darwin;FBSV/14.6.1;FBSC/arm64;FBLC/en_GB;FBBV/616513476;FBSS/1;FBID/desktop;FBWS/0;MDBeta/0;MDMas/0;MDZeratul/1] Mac Unknown