On eu u can choose between MIUI or Android notification
Inviato dal mio MIX 3 utilizzando Tapatalk
Yes, I know, doesn't make any difference.
The problems I saw on this rom were:
Native messaging app doesn't support group messaging.
Google Messages runs unreliably, messages not arriving, notifications not shown, outbound messages delayed, etc.
Lockscreen notifications not persistent.
Lockscreen notifications can't be expanded (not 100% sure about this one, may be related to lock screen security).
Getting notifications to be displayed in the first place required multiple permission screens, making debugging extremely difficult.
Now I've switched to the Pixel Experience rom, it's like night & day as far as notifications go. They worked right out of the box, and have been working fine ever since.