"Ext.view.NodeCache" is scrolling 0 records (newRecords is an empty Array) in certain test cases. No test case available can reproduce this locally in our Gantt chart.

Code:



scroll: function(newRecords, direction, removeCount) {
        var me = this,

Also, row height sync should not be performed in "Ext.grid.plugin.BufferedRenderer#onRangeFetched"

Need an extra check here if syncRowHeight is enabled



Code:



if (lockingPartner && !lockingPartner.disabled && !fromLockingPartner) {
            
            lockingPartner.scrollTop = lockingPartner.position = me.scrollTop;
            partnerNewRows = lockingPartner.onRangeFetched(null, start, end, options, true);
            if (lockingPartner.bodyTop !== newTop) {
                lockingPartner.setBodyTop(newTop);
            }
            
            lockingPartner.view.setScrollY(me.scrollTop);
            if (variableRowHeight) {
                me.syncRowHeights(newRows, partnerNewRows);
            }
        }