Support alternative lock screen

Also adds some rules for the Compton configuration so, that the lock screen
isn't transparent.

configs/laptop/misc/.config/i3/config.device

@@ -16,3 +16,6 @@ bindsym XF86AudioNext exec --no-startup-id playerctl next
 # screen brightness controls
 bindsym XF86MonBrightnessUp   exec xbacklight -inc 15
 bindsym XF86MonBrightnessDown exec xbacklight -dec 15
+
+# suspend laptop
+bindsym Ctrl+Escape exec systemctl suspend

configs/shared/misc/.config/compton.conf

@@ -10,5 +10,15 @@ inactive-opacity = 0.8;
 
 # transitions
 fading = true;
-fade-in-step = 0.03;
-fade-out-step = 0.03;
+fade-in-step = 0.07;
+fade-out-step = 0.07;
+
+# lock screen
+# NOTE: Need this rule here because I set XSECURELOCK_NO_COMPOSITE=1 in
+# ~/.profile. Without this, the lock screen will adopt the opacity settings
+# above, which is a security risk if you lock your screen while it has sensitive
+# content on it.
+#
+# NOTE: For some reason, `100:class_g` doesn't work, so settling for
+# `99:class_g` instead.
+opacity-rule = [ "99:class_g = 'xsecurelock'" ];

configs/shared/misc/.config/i3/config.shared

@@ -120,8 +120,8 @@ bindsym $mod+v split vertical
 bindsym $mod+Shift+v split horizontal
 
 # lock the screen (Window's famous Ctrl-Alt-Delete)
-bindsym $mod+Ctrl+Delete exec "/usr/share/goobuntu-desktop-files/xsecurelock.sh"
-bindsym $mod+Shift+q     exec "/usr/share/goobuntu-desktop-files/xsecurelock.sh"
+bindsym $mod+Ctrl+Delete exec xsecurelock
+bindsym $mod+Shift+q     exec xsecurelock
 
 # sound applet
 exec --no-startup-id gnome-sound-applet

configs/shared/shell/.profile

@@ -18,6 +18,13 @@ export FZF_CTRL_T_COMMAND="$FZF_DEFAULT_COMMAND"
 export DOTFILES="$HOME/Dropbox/dotfiles"
 export ORG_DIRECTORY="$HOME/Dropbox/org"
 
+# Prevent compton from fading to the lock screen. This also prevents the white
+# overlay that compton was causing to appear. Still unsure why that was
+# happening.
+# For more information, see the following GitHub issue:
+# https://github.com/google/xsecurelock/issues/28
+export XSECURELOCK_NO_COMPOSITE=1
+
 # This fixes nixpkgs that rely on glibc-2.27, which allegedly breaks locale
 # issues.
 # See this thread for more details: https://github.com/NixOS/nixpkgs/issues/8398

configs/shared/x_server/.xsessionrc.shared

@@ -6,6 +6,9 @@ export DESKTOP_SESSION=cinnamon  # gnome for trusty.
 
 # NOTE: This may break your compose key.
 # See http://g/i3-users/YBexXGbik7E for more details.
+# NOTE: IM_MODULE is an "Input Method" module, which I believe affects the way
+# keyboard events are processed. `xim` is "X Input Method"; other options
+# include: `ibus`, `fcitx`, but I'm unsure what features each offers.
 export GTK_IM_MODULE=xim
 
 # Desktop background color.
@@ -23,7 +26,7 @@ clipmenud &
 # Start the Emacs server
 emacs --daemon
 
-# start comption
+# start compton for shadows, transparency, fading, etc.
 compton &
 
 # set kbds