Latest Facebook Messenger 234 user agents:

User Agent Platform Device
Mozilla/5.0 (Linux; Android 9; ZB602KL Build/PKQ1; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/77.0.3865.92 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/234.0.0.9.121;] Android 9 ZenFone Max Pro M1
Mozilla/5.0 (Linux; Android 8.1.0; ASUS_X00LD Build/OPM1.171019.011; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/77.0.3865.92 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/234.0.0.9.121;] Android 8 ZenFone 4
Mozilla/5.0 (Linux; Android 8.0.0; SM-G930T Build/R16NW; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/77.0.3865.92 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/234.0.0.9.121;] Android 8 Galaxy S7
Mozilla/5.0 (Linux; Android 8.0.0; SM-G930L Build/R16NW; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/77.0.3865.92 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/234.0.0.9.121;] Android 8 Galaxy S7
Mozilla/5.0 (Linux; Android 6.0; ALE-L21 Build/HuaweiALE-L21; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/77.0.3865.92 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/234.0.0.9.121;] Android 6 P8 Lite (2015)
Mozilla/5.0 (Linux; Android 6.0.1; vivo 1606 Build/MMB29M; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/55.0.2883.91 Mobile Safari/537.36 [FB_IAB/Orca-Android;FBAV/234.0.0.9.121;] Android 6 Y53i