This TWRP for Mi Mix 2 is built as system-as-root.
Starting from Android 10, the rootfs is going to be a part of system which is called as system-as-root.
It is important for Mi Mix 2 users flashing any custom ROM based on Android 10 or LineageOS 17 must use system-as-root supported TWRP.
Here is a direct link to download system as root TWRP for Mi Mix 2 which is required for Mi Mix 2 LineageOS 17 custom ROM and other Android 10 based custom ROMs.
