Hi, I've discovered that the non-working brightness controls for the MacBook2,1 are due to insufficient permissions.
The first indication of this was that I could change brightness by running the program redshift with root permissions (`sudo redshift`). Today I was presented with this dialog box in GNOME 3 after having pressed one of the brightness-control keys: "Authentication is needed to run '/gnu/store/[...]-gnome-settings-daemon-3.18.2/libexec/gsd-backlight-helper' as the super user. Administrator Password [__________]" I tried to input both the user password and the root password but none of this this had any effect. When I back into GNOME 3 as root, however, the brightness controls were working. Does anyone have a suggestion what I could try to give the various brightness control programs (for GNOME 3, Xfce, etc.) the required permissions without having to be logged in as root? Cheers! Albin