This method is based on Amazing Temp Root for MediaTek ARMv8 by diplomatic
Clever work that give MTK-soc devices a bootless root ( Root remains until reboot ). And lucky enough it works on our Nokia 5.1 Plus
So to begin :
-Grab diplomatic lastest mtk-su.zip in Amazing Temp Root for MediaTek ARMv8
- Follow instructions from Bootless root with Magisk and MTK-SU
#You can install Magisk Manager from the magisk 18.1 package, or any version below 7.1.2. Lastest version of MM doesn't work.
And your device should have root permission.