What incorrect behavior happened?

Lost all changes in a job

Environment
O.S.: Linux,Mac OSX
CJE version: Jenkins ver. 2.7.19
Web browser:
JDK version: JDK8

What was the expected outcome?

Should save the changes

Step by step to reproduce it

1. Create a Job
2. Open a terminal and execute an script to read every 1 s the config.xml of the job
3. Add one step to the job and check the terminal to see if the step is in the config
4. Repeat the previous step until all steps was removed

The script

while [ true ]; do curl http://cje.example.com:8080/job/fsj/config.xml; sleep 1s;  done

Video of how to do that

https://drive.google.com/open?id=0Bz36P9uZT4syR0V0RGFNbzJubzQ