Comment # 8 on bug 960360 from Egbert Eich

I have the impression that your desktop is interfering here somehow.
Could you please run a test from the console for me?
Please remove / comment out the udev rule for that!

1. log out of your desktop session
2. Change to a text console: ctrl-alt-f<N>  for instance <N>=3
3. log in as root
4. run 'systemctl stop display-manager.service'
5. save the script below to a file test.sh
6. execute: 'chmod u+x test.sh'
7. run './test.sh' and get me the output of /tmp/diff-before-after

#!/bin/sh

export DISPLAY=:1
X :1 2>/dev/null & 
pid=$!
sleep 2
xterm & 
sleep 1
synclient -l > /tmp/before;
synclient TouchPadOff=1
synclient -l > /tmp/after
kill $pid
diff /tmp/before /tmp/after > /tmp/diff-before-after