(20.04) Brightness keys not working after intel 'tearfree' fix

Title pretty much says it - but in detail, I deployed the intel tear free true fix:
sudo nano /etc/X11/xorg.conf.d/20-intel.conf

Section “Device”
Identifier “Intel Graphics”
Driver “intel”

Option “TearFree” “true”

Also previously had the following but removed as some threads note that it not needed (current testing confirmed not needed for tearfree):
sudo nano /etc/X11/xorg.conf
Section “Device”
Identifier “Intel Graphics”
Driver “intel”

this stops brightness keys from working but brightness gui changes brightness with slider as expected. If I remove the 20-intel.conf (previously xorg.conf as well but not currently in play) and reboot the keyboard shortcuts function as normal.

Checked the keyboard shortcuts to show they are calling the following commands:

lxqt-config-brightness -i 
lxqt-config-brightness -d 

From the command line lxqt-config-brightness up and down do not work but -s to set to a specific percentage does. Later testing shows if I use ‘sudo’ for the above lxqt commands backlight will change. Using this and some creative googling I found the _backend commands.

These commands appear to work from command line (found on an ubuntu forum thread):

pkexec lxqt-backlight_backend --inc
pkexec lxqt-backlight_backend --dec

Added those commands to the brightness shortcut keys and the keys still do not function. Added custom keys win+alt+up/down still do not work.

Resorted to creating bash scripts on the desktop to double click brightness up and down with the _backend commands instead of having to launch brightness gui all the time. Probably dumb but it works for the moment even if its not a permanent solution.

If I tail -f the /var/log/syslog I can see nothing happening when I press the keys but if I use pkexec lxqt-config-brightness_backend or sudo lxqt-config-brightness from the command line syslog sees it.

Lubuntu 20.04
Thinkpad T440p
Intel i5-4300M CPU @ 2.60GHz
Intel HD Graphics 4600

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 20.04 LTS
Release:        20.04
Codename:       focal

I do not know enough about X11 or lxqt-config-brightness to understand why it is failing only when I specify the 20-intel.conf — I am assuming I am changing away from some hard defined variable somewhere and all I would have to do it point it to the proper changed information. I figured brightness change keys should work since I located the command that will change the brightness but adding the _backend commands to the shortcut keys does not function so it looks a little bit deeper than I have been anticipating.

I can’t seem to figure out what the disconnect is adding the intel file with ‘tearfreee’. I get that it broke but I am missing a tie in because logically in my head I should be able to pass the shortcut one of the strings that WILL change the brightness. But the other function keys seem to be unaffected. Im just lost at this point.

I am sure this is probably simple stuff to the seasoned linux crowd but looking to learn if anyone is willing to teach a little bit.

Happy to provide logs and command output as needed but I didn’t want to clutter up the post if this is just a simple ‘go here’ sort of situation. Thanks in advance guys!

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