As this utility is a community package and as such it can not be put on the list of the user package list of EOS or something like that. (It’s quality-control in some respect I guess)
I heard that we are living in an agile age or times so do not wait for others to solve your problem.
If you need a live bootable image to test displays I see 3 options:
- POP!_OS_22_04 provides this in Live mode Fn + F12, Fn + F11 (boot is not so fast as that of EOS)
- Use Lilidog (Debian 11) https://forum.endeavouros.com/t/ein-damn-small-linux-mit-eos/37521/18
Needs cubes to customize Live image.
Additional note: In wizard when you enter virtual environment terminal:
# apt-get update
# apt install brightnessctl
This is the 2nd fastest solution I know.
3. If you insist on an arch based system, a bit more time consuming process (for your machine)
to install https://arcolinuxb.com/byoi-on-arcolinux-xfce/ add a line:
brightnessctl to ~/arco-xfce/archiso/packages.x86_64
and Build Your Own Iso (BYOI) with the 30…sh script It takes cca. 40 minutes.
4.
Install EOS to a flash drive (with enjoyable speed like Samsung 128 GB FIT Plus)
Re @huffin 's question.