First of all a big thank you to all DEV's for another amazing work. The
xiaomi.eu_multi_MI10Pro_V12.1.2.0.RJACNXM_v12-11.zip works like a charm.
I first had many problem, when i upated from stable 12.0.4 to this by OTA, i think it was v1 my mobile data not work. I remember to had the same problem in weekly
xiaomi.eu_multi_MI10Pro_20.8.7_v12-11.zip all versions, and i thought then, it's the beta, it can be always something. Very disappointed when it was the same in stable and i went back to 12.0.4. Then i read there is updated versions v2-3 and i gave it a try again friday night, but the same problem. So went back again. Then i recognized the blue icon in the statusbar when the phone receaves the mobile network data, it apears very short just a flash, and i thought maybe the modemfile could be corrupted (Switzerland - Swisscom). Saturday give it a try again. Tried with a Tesco Mobile UK prepaydcard the mobile data can work. As magisk can not easily install on android 11 and i need root for the PDC tool it was a little tricky. Deleated the swisscom file and activated vodafone germany, and hurray mobile data worked also VOLTE and VOWIFI. would be fine to use the original file if it could fixed in the next update. Then i recognized many problems like other users described. Verry Laggy system and apps, apps crashed or open by them self, Audio and or videos shuttering in youtube, firefox and even on the phone stored files and ringtones. The phone was unusable. and randomly reboot it self. A dirty reflash helped nothing. Then i decided in TWRP a format data and after first boot, skip googleaccount, and deny restore from xiaomi clud. the telephone worked normal. went back to TWRP and format data again and choose restore google backup and xiaomi cloud and surprise, the phone works like a charm and very fluent.
I use the MI 10 PRO CN 12/512GB