Applications lost permissions after flashing Marshmallow
For me the boot.img modification by Chainfire worked partially: device seems to be rooted (with supersu 2.51 beta), but twrp asks for password and cannot mount anything (I've posted a question about the latter). In particular I could not install supersu via adb sideload from recovery, as Chainfire recommends. Rather I just installed apk from system (using simple explorer).