I am using Xubuntu 15.04 with Xfce 4.12 in a Dell Inspiron 14 laptop, model 3442. Whenever I lock my screen, then put my password and unlock it, the screen brightness gets very low, it's almost as if the screen is turned off. In order to fix this, I open the 'Display' window and change the screen to a different resolution and back again.
I've read similar problems as well as an official post in the Xubuntu blog. They basically say to open 'Light Locker Settings' and turn Light Locker off and on. However, in my system, Light Locker Settings was not originally installed. I installed the
light-locker-settings package via apt-get, opened the application and it said that my screensaver settings were managed by 'Xfce Power Manager'. I turned Light Locker off and on anyway, but my problem is not solved. Any thoughts?
Edit: I just found out it looks like this is a known bug (1259339) that dates back to 2013. It is also mentioned in the Xubuntu 14.04 release notes, but not in the 2015 release notes, even though it seems not to be fixed. Sorry, I don't have enough reputation to link to these pages I mentioned.