Null values breaks sorting

I’ve noticed that if the JSON data has null values for some of the grid columns it breaks the built-in sorting.

I’ve worked around this by replacing the nulls with ‘N/A’ on the server-side, but is this expected behaviour?

Hello Mat,
I don’t see any issues if there are null or empty fields in the data:
http://snippet.dhtmlx.com/5/6e951e20f
Probably, it is related to Gantt configuration, but it is hard to suggest what might be wrong as I don’t see your code.
Please, reproduce the issue in the snippet, then click on the “Share” button and send me the link:
https://snippet.dhtmlx.com/38ee1b370
Or send me an HTML file with all the necessary Javascript and CSS files.