No longer supported. It might or might not work for your use case.

Backlight Tracer

Small service tracking backlight state and restoring it on power change. This mean battery and AC have a separate brightness level and the same is restored once power state changes. Essentially the same thing for Ubuntu that the Windows already have.

Currently it only supports Intel cards.

Linux Debian Repository Installation
wget -O- http://packages.medo64.com/keys/medo64.asc \
    | sudo tee /etc/apt/trusted.gpg.d/medo64.asc

echo "deb http://packages.medo64.com/deb stable main" \
    | sudo tee /etc/apt/sources.list.d/medo64.list

sudo apt-get update
sudo apt-get install backlight-tracer
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