Change picom conf location and add launching script

.config/i3/config

@@ -572,4 +572,4 @@ exec --no-startup-id $i3-wm.program.3
 # Start polybar
 exec_always --no-startup-id ~/.config/polybar/launch.sh &
 exec_always --no-startup-id feh --bg-scale ~/Images/skyscape-4.jpg
-exec_always --no-startup-id picom --experimental-backends
+exec_always --no-startup-id ~/.config/picom/launch.sh &

.config/picom/launch.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env sh
+
+# Terminate already running picom instances
+killall -q picom
+
+# Wait until the processes have been shut down
+while pgrep -u $UID -x picom >/dev/null; do sleep 1; done
+
+# Start picom
+picom --experimental-backends