When I have my monitor connected by HDMI and I start the system, the login screen appears normally. I log in and the wallpaper shows up, but anything else. After a few seconds (like 5 or 10 seconds) the login screen shows up again, like anything happened. After I log in the second time everything is alright and I can work normally.
This is only happening if the monitor is plugged in. Otherwise, the first login is ok. May be a driver issue?