Working with Dell laptop often it is left with lock screen when i am afk. After some idle time screen brightness is lowered by system to save power. When i return and move cursor or unlock screen, original brightness is not restored so i have to do it manually. Reproducible: Always Steps to Reproduce: 1. Lock screen 2. Leave laptop unused for some time 3. Try to move cursor and unlock screen Actual Results: Original brightness is not restored - screen stays darker. Expected Results: System should restore original screen brightness that was set bofore it went to idle.
I have exactly the same problem on a Dell latitude E6540 If I can add some more informations let me know.
Kubuntu 15.04 Kde platform version 4.14.8 Kde plasma version 5.3.2 Qt version 5.4.1 Kernel: 3.19.0-30-generic (64bit)
I can also confirm this on kubuntu 15.10, both with default plasma 5.3 install and with plasma 5.5 from backports ppa.
I can confirm this on Kubuntu 16.04 with plasma 5.5.5.
Some more info: Lenovo Yoga 2 Pro @ 1920x1080 Kernel: 4.4.0-24-generic
I have a kind of the same issue. I use a two monitor-setup (laptop-screen and an external monitor connected by hdmi) When udimming after the screens are dimmed after 5 min. of inactivity, the laptop screen comes back with full brightness. I then have to click on the battery icon in the tray, and the indicator still shows the minimum brightness (which is my choice). As soon as I move the indicator (slider) a bit, it lowers the brightness to the set level. First bug: The brightness should not change after the screen dims. Second bug: After dim happens, the indicator shows minimum brightness even it's set to full. As soon as I move it it goes back to the value actually set by the indicator.
*** This bug has been marked as a duplicate of bug 352497 ***