zk.afterLoad('zul.mesh, zkmax', function() {
    var xFrozen = {};
    zk.override(zul.mesh.Frozen.prototype, xFrozen, {
        _findFrozenCols : function(frozenColNum, rowNodes, rowIndex, nextRowSpanArr) {
            var spanLookup = this._buildSpanLookupTable(frozenColNum, rowNodes);
            //console.log(spanLookup);
            //var result = xFrozen._findFrozenCols.apply(this, arguments);
            var cellInfos = spanLookup[rowIndex];
            var cellsInRow = cellInfos
                                .filter(cellInfo => cellInfo[1] === rowIndex)
                                .map(cellInfo => cellInfo[0]);
            var numFrozenCellsInRow = new Set(cellsInRow).size;
            return numFrozenCellsInRow;
        },
        _buildSpanLookupTable: function(frozenColNum, rowNodes) {
            var spanLookup = [];
            for(var i = 0; i < rowNodes.length; i++) { spanLookup[i] = []; }
            rowNodes.forEach((rowNode, rowIndex) => {
                var cellNodes = rowNode.childNodes;
                var colIndex = 0;
                cellNodes.forEach(cellNode => {
                    while(spanLookup[rowIndex][colIndex]) {
                        colIndex++; //adjust colIndex by previous rowSpans
                    }
                    if(colIndex < frozenColNum) {
                        var colSpan = cellNode.colSpan || 1;
                        var rowSpan = cellNode.rowSpan || 1;
                        for(var i = 0; i < rowSpan; i++) {
                            for(var j = 0; j < colSpan; j++) {
                                spanLookup[rowIndex + i][colIndex + j] = [cellNode, rowIndex, colIndex];
                            }
                        }
                    }
                });
            });
            return spanLookup;
        }
    });//zk.override
});//zk.afterLoad