I apologise for the delay with the reply.
Thank you for your report. The problem was confirmed. We’ll try to fix it in one of the future updates.
I’ll inform you about any progress on this issue.
We fixed your reported problem in the latest dhx.Suite update (v8.3.4.)
Now the beforeSort event should work properly.
You can test it in your original snippet.
Please, download the latest available dhx.Suite build from your client’s area to get this fix.
Thank you for your report.
Best regards.
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