We have fixed your report problem with the custom scroll in the grid with the frozen column(rows) in the latest dhtmlxSuite update (v8.0.1.)
You can test it in the following snippet: https://snippet.dhtmlx.com/1nsqd7e2
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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