You can find below known Mi5 Oreo issues summarized (might be Oreo builds for other devices also affected), so no need to posting repeatedly all the time the same issue:
1. In split screen mode scrolling for second app in recent apps tray causes system UI FC
2. No vibrate no sound for Tapatalk notifications
3. Additional settings > Privacy > Managed device info: most of the options cant be opened under this menu
4. Quick card > Notes: Chinese text visible
5. Security app > Data > Top Up: Chinese texts visible
6. No vibrate for Gmail notifications, there is only sound
7. Gmail > Settings >
account@gmail.com > Manage notifications: Vibrate and Blink light options always switch back to disabled after exiting menu
8. Gmail > Settings >
account@gmail.com > Manage notifications: "On the lock screen" option cant be opened
9. Settings > Sound & Vibration: Ringtone and notification sounds options lead to pre-installed system themes instead of sound options
10. Camera: "Mirror front camera" options (ON, OFF, When face detected) don't have any effect on front camera
11. Mixed system animation speeds (opening folders animation is faster, opening app animation is slower)