Latest Opera 57 user agents:

User Agent Platform Device
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3489.17 Safari/537.36 OPR/57.0.3324.76 Windows Vista Unknown
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3483.26 Safari/537.36 OPR/57.0.3331.38 Windows Vista Unknown
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3477.43 Safari/537.36 OPR/57.0.3328.61 Windows Vista Unknown
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3472.28 Safari/537.36 OPR/57.0.3335.16 Windows Vista Unknown
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3427.16 Safari/537.36 OPR/57.0.3346.78 Windows Vista Unknown
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3423.41 Safari/537.36 OPR/57.0.3385.33 Windows Vista Unknown
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3417.19 Safari/537.36 OPR/57.0.3344.73 Windows Vista Unknown
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.7.3174.18 Safari/537.36 OPR/57.0.3944.14 Windows Vista Unknown
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.4.3480.13 Safari/537.36 OPR/57.0.3924.66 Windows Vista Unknown
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.4.3471.24 Safari/537.36 OPR/57.0.3976.31 Windows Vista Unknown
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.4.3427.25 Safari/537.36 OPR/57.0.3940.95 Windows Vista Unknown
Mozilla/5.0 (Windows NT 6.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.4.3411.55 Safari/537.36 OPR/57.0.3972.43 Windows Vista Unknown
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36 OPR/57.0.3098.91 (Edition Campaign 34) Windows 10 Unknown
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36 OPR/57.0.3098.116 Windows 10 Unknown
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36 OPR/57.0.3098.102 Windows 10 Unknown
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36 OPR/57.0.3098.116 Mac 10 Unknown
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36 OPR/57.0.3098.106 Mac 10 Unknown
Mozilla/5.0 (Linux; U; Android 7.0; TECNO P904 Build/NRD90M; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/91.0.4472.120 Safari/537.36 OPR/57.0.2254.57961 Android 7 DroidPad 10D 4G
Mozilla/5.0 (Linux; U; Android 7.0; PMT3327_3G Build/LMY48B; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/91.0.4472.120 Safari/537.36 OPR/57.0.2254.58007 Android 7 Wize 3327 3G
Mozilla/5.0 (Linux; U; Android 11; POCO M2 Pro Build/RQ2A.210505.003; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/90.0.4430.210 Safari/537.36 OPR/57.0.2254.58007 Android 11 M2 Pro