Mozilla/5.0 (Linux; U; Android 9; ru-ru; NX569J Build/PQ3A.190605.003) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/61.0.3163.128 Mobile Safari/537.36 XiaoMi/Mint Browser/2.4.0

Mozilla/5.0 (Linux; U; Android 7.0; ru-ru; Lion_Dual Build/NRD90M) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/61.0.3163.128 Mobile Safari/537.36 XiaoMi/Mint Browser/3.3.1

Mozilla/5.0 (Linux; U; Android 7.0; ru-ru; localhost Build/NRD90M) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/61.0.3163.128 Mobile Safari/537.36 XiaoMi/Mint Browser/3.1.4

Mozilla/5.0 (Linux; U; Android 7.0; ru-ru; Impress_Wolf Build/NRD90M) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/61.0.3163.128 Mobile Safari/537.36 XiaoMi/Mint Browser/3.3.1

Upd 1
https://play.google.com/store/apps/details?id=com.mi.globalbrowser.mini&hl=en
It seems we can no longer rely on Xiaomi's definition since this browser can install any device