onChange keeps doubling up the stroks

[darshanmarathe]

Describe the bug
I am trying to develop a whiteboard (multiuser) for my open-source interview pad aka codecollab project
https://interviewpad.collabmantra.com/001

To Reproduce
Steps to reproduce the behavior:

1. Go to "interviewpad'
2. Click on Inspect > Open Console >
3. On UI click sketch tab and draw few lines u will see
4. See error

Expected behavior
it should not keep doubling it up

https://github.com/darshanmarathe/CodeCollab