How to find out difference between 2 cells?

I have functionality where I am copying one cell value to another cell for which I need to know the source and destination cell , so that I can find the difference , and whatever the difference may be will be used to update some formula.
Can you help to find source and destination cell and their difference?

Hello @priyatama,

There is pretty much no way to get the source cell position besides the onItemClick event (or something like onAfterBlockSelect for that matter), which means that you will, unfortunately, have to use global variables and verify the position of the cell that was copied. After that, pretty much everything else can be done with the help of the onBeforeValueChange event, which will tell you the destination cell position and its value.

Here is a rough example of how this might work: https://snippet.webix.com/mlnqko1n.