Bug report

Reproduction of the problem

Reproducible in this demo: https://demos.telerik.com/kendo-ui/spreadsheet/datasource

1. Scroll down to row 78
2. Focus A78 and drag to E78. Copy the data
3. Paste over the empty 79 row's first cell
4. Press Ctrl + Z to undo the changes.
5. Open the browser's dev tools network tab and press the "Save" button above the Spreadsheet.

Current behavior

The data cleared by the "undo" shortcut is saved and sent to the server

A different behavior is exhibited if the data is pasted over the row header instead of the row's first cell. Follow the same steps, but on step 3. instead of pasting over the first cell, paste the data over the row 79 header. After undo and then clicking "Save", the fields have null values.

Expected/desired behavior

No data is sent with the request

Environment

• Kendo UI version: 2020.2.617
• jQuery version: x.y
• Browser: [all]