Just received my framework 13 a week ago and have already installed the Cinnamon edition of Linux Mint 21.2 “Victoria” and have noticed that I am unable to adjust my screen brightness. With closer inspection using brightnessctl, this is the output:

Device ‘phy0-led’ of class ‘leds’:

Current brightness: 1 (100%)

Max brightness: 1

This is my failed attempt using xrandr:

xrandr: Failed to get size of gamma for output default

Screen 0: minimum 2256 x 1504, current 2256 x 1504, maximum 2256 x 1504

default connected primary 2256x1504+0+0 0mm x 0mm

2256x1504 95.00*

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Any suggestions on how to solve this if it can be?