I check with Linux Mint(Debian) and Manjaro Linux (Arch Linux). When I press 'Fn_key + Win_Key' the system shutdown at the spot without any confirmation and interesting thing is that if I press this key combination even at the login screen (after system restart) the system will shutdown. While when I login into KDE DE and press this key combination this is not happening. This problem occur when I am on Awesome WM and on login-screen. Many people suggested it's out of control of OS and something at kernel level. As on below image it showing something related to systemd like that.
Sometimes ago I thought it was problem with Awesome WM, but close inspection on system log reveals that 'power key is pressed' and this confuses me until now when I found the right key combination for this shutdown. Also Awesome WM developers said it's beyond the control of Awesome WM and something at kernel level. This is true, because I can shutdown even at my login-in screen as at that time no Desktop Environment or Window Manager is yet loaded. I am confused is this built-in shortcut like something related to "Linux Magic System Request Key", but based on the documentation it's SysRq key.
A quick update when I press the key combination in Linux Mint Cinnamon Desktop it pop this confirmation as in below picture, while KDE Desktop on Manjaro it doesn't work at all. For Awesome WM on both Debian and Arch Linux it work without confirmation. Also in login screen of both Linux Distro no confirmation, direct shutdown. So really this is any shortcut in Linux Kernel level ??
