gistfile1.txt

#!/bin/bash
old=""
while true; do
	new="$(xdotool getwindowfocus)"
	if [ "$old" != "$new" ]; then
		echo a
		# Tried both windowfocus and windowactivate
		xdotool \
			search --onlyvisible --class '^Plasma$' \
			windowfocus --sync \
			windowfocus --sync "$new" \
			getwindowname "$new"
		echo c
		#  "$(xdotool search --onlyvisible --class '^Plasma$' | head -n 1)" 
	fi
	old="$new"
	sleep 0.1
done