Acumatica uses C# exception mechanism to redirect to another web page (the report launcher is a web page).

You can create a customization with a graph extension that intercept the report redirect exception. Then you can modify the WindowMode property to New and rethrow the report redirect exception.

Source code for this solution:

using PX.Data;
using System;
using System.Collections;

namespace PX.Objects.SO
{
    public class SOShipmentEntry_Extension : PXGraphExtension<SOShipmentEntry>
    {
        public delegate IEnumerable ReportDelegate(PXAdapter adapter, String reportID);
        PXOverride]
        public IEnumerable Report(PXAdapter adapter, String reportID, ReportDelegate baseMethod)
        {
            if (reportID == "SO642000")
            {
                IEnumerable returnValue = adapter.Get();

                try
                {
                    returnValue = baseMethod(adapter, reportID);
                }
                catch (PXReportRequiredException ex)
                {
                    ex.Mode = PXBaseRedirectException.WindowMode.New;
                    throw ex;
                }

                return returnValue;
            }
            else
            {
                return baseMethod(adapter, reportID);
            }
        }
    }
}