Lockscreen shows black screen on Kali linux multimonitor setup
In Kali Linux 2020.3 with XFCE4 installed whenever I lock the screen on my 3 monitor setup I get a blank screen. However if I type the password in blindly, it logs me in, altough it doesn't work 100% of the time.
This is also the same issue mentioned here but since I don't have enough reputation I can't answer it. I decided to ask state the question and answer it myself instead.
1 Answer
After a bit of digging I found that it's actually an XFCE4 issue.
Upon lock /usr/bin/xflock4 is called which is just a script with a bunch of lock commands.
For me it was the case that light-locker-command --lock simply doesn't work with multi monitors.
The solution is to simply install xscreensaver and it will take precedence over the light-locker-command. Make sure you execute xscreensaver -nosplash and also add it to in Session and Startup for this to work.
Note: If the command xfconf-query -c xfce4-session -p /general/LockCommand returns something else than not empty, then that should be configured instead to your favorite lock app.
