What is Magisk Manager?
It is a match for a mask to give root permissions without altering or modifying the system files.
It is the best alternative to SuperSU so that installing SuperSU may make you have problems with most apps that don't work with root.
As for Magisk Manager, it works to hide the root from the applications that do not work with the presence of the root and this is what users prefer in addition to it is open source and this is what the developers love.
Link: