I am now following the steps on https://wiki.ubuntu.com/Kernel/Debugging/Backlight
The first step was to reboot with default Linux parameters. I had been using "acpi-backlight=vendor". When I took that out and rebooted, the symptoms changed: the hotkeys no longer make the slider on the pop-up brightness widget go up and down. And they still also don't change the screen brightness. Anyway, I'll be attaching the files requested on that page for debugging. 1. ls /sys/class/backlight > backlight ** Attachment added: "backlight" https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1214148/+attachment/3778478/+files/backlight -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1214148 Title: Intel video: Display backlight cannot be changed on Toshiba Portege Z935 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1214148/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
