请参阅代码示例和附加的小提琴。
问题：基本上，从Chrome 81开始，甚至在此之前，我们应用程序的用户就报告了Ext.grid.Panel getHeaderContainer（）.insert不工作的问题。基本上，当用户更改组合框中的选项时，我们会设置一些动态列。
问：有人知道这个问题的可能解决方法吗？或者知道 Sencha 是否意识到这个问题并正在进行修复？
解决办法：发现grid.columns.length在removeAll（）后不再返回0

header.insert(0, cols) works
header.add(cols) also works

ExtJS 7.2.0 Chrome 81（不再工作）Firefox 76.0.1（工作）边缘（非 chrome ）（工作）
Sencha 小提琴：https://fiddle.sencha.com/#view/editor&fiddle/35vb

Ext.application({
    name : 'Fiddle',

    launch : function() {

        Ext.create('Ext.Button', {
            text: 'Change Fields',
            renderTo: Ext.getBody(),
            handler: function(button, e) {

                var grid = Ext.getCmp('testGrid');
                console.log('grid = ', grid);

                var header = grid.getHeaderContainer();
                console.log('header Before = ', header);

               //Setup the columns for Grading Period = Semester
                var cols = [{ text: 'Student ID', dataIndex: 'StudentID'},
                    { text: 'Name', dataIndex: 'LastFirst', width: 180},
                    { text: '1st Midterm Grade', dataIndex: 'GradEntA_1', width: 140, editor: 'textfield'},
                    { text: '1st Nine Weeks', dataIndex: 'GradEntA_2', width: 140, editor: 'textfield'},
                    { text: '2nd Midterm Grade', dataIndex: 'GradEntA_3', width: 140, editor: 'textfield'},
                    { text: '2nd Nine Weeks', dataIndex: 'GradEntA_4', width: 140, editor: 'textfield'},
                    { text: '1st Exam Value', dataIndex: 'GradEntB_1', width: 140, editor: 'textfield'},
                    { text: '1st Semester Value', dataIndex: 'GradEntB_2', width: 140, editor: 'textfield'},
                    { text: '1st Semester Credit', dataIndex: 'GradEntB_3', width: 140, editor: 'textfield'},
                    { text: '3rd Midterm Grade', dataIndex: 'GradEntC_1', width: 140, editor: 'textfield'},
                    { text: '3rd Nine Weeks', dataIndex: 'GradEntC_2', width: 140, editor: 'textfield'},
                    { text: '4th Midterm Grade', dataIndex: 'GradEntC_3', width: 140, editor: 'textfield'},
                    { text: '4th Nine Weeks', dataIndex: 'GradEntC_4', width: 140, editor: 'textfield'},
                    { text: '2nd Exam Value', dataIndex: 'GradEntD_1', width: 140, editor: 'textfield'},
                    { text: '2nd Semester Value', dataIndex: 'GradEntD_2', width: 140, editor: 'textfield'},
                    { text: '2nd Semester Credit', dataIndex: 'GradEntD_3', width: 140, editor: 'textfield'},
                    { text: 'Final for Term', dataIndex: 'GradFinal', width: 140, editor: 'textfield'}
                   ];

                header.removeAll();
                header.insert(cols);

                console.log('header After = ', header);

            }
        });
        Ext.create('Ext.grid.Panel', {
            title: 'Column Demo',
            id: 'testGrid',
            width: '100%',
            columns: [
                {text: 'First Name',  dataIndex:'firstname'},
                {text: 'Last Name',  dataIndex:'lastname'},
                {text: 'Hired Month',  dataIndex:'hired', xtype:'datecolumn', format:'M'},
                {text: 'Department (Yrs)', xtype:'templatecolumn', tpl:'{dep} ({seniority})'}
            ],
            forceFit: true,
            renderTo: Ext.getBody()
        });

    }
});