Highcharts - Highstocks。显示所有x轴标签

Question

我设置了highstocks来显示两个系列的数据。

当我一直缩放时，其中一个系列的x轴标签总是丢失。

jsfiddle link

    $(function() {
        Highcharts.setOptions({
            global: {
                useUTC: false
            }
        });
        var chart = new Highcharts.StockChart({
            chart: {
                "renderTo": "container"
            },
            plotOptions: {
                "column": {
                    "stacking": "normal"
                }
            },
            series: [{
                "type": "column",
                "name": "column 1",
                "color": "#1d8ecd",
                "data": [
                    [1296511200000, 974],
                    [1301605200000, 1618],
                    [1306875600000, 990],
                    [1312146000000, 1720],
                    [1317416400000, 516],
                    [1322690400000, 1472],
                    [1328047200000, 349],
                    [1333227600000, 1781],
                    [1338498000000, 649],
                    [1343768400000, 1124],
                    [1349038800000, 829],
                    [1354312800000, 1615],
                    [1359669600000, 1181]

                ]

            }, {
                "type": "column",
                "name": "column 2",
                "color": "#636466",
                "data": [
                    [1293832800000, 1913],
                    [1298930400000, 1269],
                    [1304197200000, 567],
                    [1309467600000, 668],
                    [1314824400000, 722],
                    [1320098400000, 442],
                    [1325368800000, 1558],
                    [1330552800000, 1831],
                    [1335819600000, 373],
                    [1341090000000, 275],
                    [1346446800000, 1540],
                    [1351720800000, 998]
                ]
            }],

        });
    });

任何想法为什么会发生这种情况，如果我可以强制它显示所有x轴标签，至少在有空间的时候？