With recent MATE 1.18 sensors applet doesn’t show hddtemp sensor, although libhddtemp.so exists and hddtemp works under user in “disk” group:
~$ dpkg -L mate-sensors-applet |grep hddtemp
/usr/lib/x86_64-linux-gnu/mate-sensors-applet/plugins/libhddtemp.so
~$ hddtemp /dev/sda
/dev/sda: Hitachi HDP725050GLA360: 38°C
With previous MATE versions (gtk2) I hadn’t this issue. Can anyone confirm this behavior?