I thought, this whould be useful:
Root access is no longer working (developer settings - ROOT access - there is only ADB option). Also I have flashed SuperSU from the OP but this does not appear to be working as well. I tried to do this on a dirty install (upgrade from previous version) and then to make sure on a clean install. I know, that the previous build had none of these issues. Is anybody having the same issue?
I've made a full wipe install and installed SuperSU 2.79 and no problem with root access.
I've never tried root from developer options.