I got a little further with this. I found that lxqt-config-brightness is the prorgram that is called when you press brightness up or down.
RUnning this on the terminal reveals the following: lxqt-config-brightness -r (0x7ffe7dcde2b0) Debug: No outputs have backlight property (0x7ffe7dcde2b0) Debug: Found output: "eDP" (0x7ffe7dcde2b0) Debug: Output: "eDP" added (0x7ffe7dcde2b0) Debug: Found output: "HDMI-A-0" (0x7ffe7dcde2b0) Debug: Output is not connected Note the message about backlight. Yet in all other Ubuntu flavours, and indeed the Brightness control panel on LXQT itself, I can adjust the backlight!! -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1829641 Title: brightness keys on laptop don't dim the backlight To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lxqt-powermanagement/+bug/1829641/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
