How to add custom items with default items in Context Menu of handsontable

I tried to use handsontable and want to add custom items to context menu.

There are many tutorials to implement custom menus, but it ignores the default items.

So I added keys of all items, but some of them don't work.

My setting is like follows.

var basicSettings = {
    minRows: 1,
    minCols: 1,
    rowHeaders: false,
    colHeaders: false,
    hiddenColumns: true,
    contextMenu: {
        items: {
            row_above: {},
            row_below: {},
            "hsep1": "---------",
            col_left: {},
            col_right: {},
            "hsep2": "---------",
            remove_row: {},
            remove_col: {},
            "hsep3": "---------",
            undo: {},
            redo: {},
            "hsep4": "---------",
            make_read_only: {},
            "hsep5": "---------",
            alignment: {},
            "hsep6": "---------",
            copy: {},
            cut: {},
            "paste": {
                name: 'Paste',
                callback: function (key, option) {
                    this.copyPaste.triggerPaste();
                }
            },
            "hsep7": "---------",
            mergeCells: {
                name: "Merge"
            },
            "hsep8": "---------",
            // Custom menu item to set color of cells
            set_color: {
                key: "color",
                name: "Color",
                "submenu": {
                    "items": [
                        {
                            key: "color:1",
                            "name": "Black",
                            callback: function(key, options) {
                                for (var i = options[0].start.row; i <= options[0].end.row; i ++){
                                    for (var j = options[0].start.col; j <= options[0].end.col; j ++){
                                        this.getCell(i, j).className = "color-black";
                                    }
                                }
                            }
                        }, {
                            key: "color:2",
                            "name": "White",
                            callback: function(key, options) {
                                for (var i = options[0].start.row; i <= options[0].end.row; i ++){
                                    for (var j = options[0].start.col; j <= options[0].end.col; j ++){
                                        $(this.getCell(i, j)).removeClass("color-*").addClass("color-white");
                                    }
                                }
                                this.render();
                            }
                        }, {
                            key: "color:3",
                            "name": "Red",
                            callback: function(key, options) {
                                for (var i = options[0].start.row; i <= options[0].end.row; i ++){
                                    for (var j = options[0].start.col; j <= options[0].end.col; j ++){
                                        this.getCell(i, j).style.backgroundColor = "red";
                                    }
                                }
                                this.render();
                            }
                        }
                    ]
                }
            }
        }
    },
    manualRowResize: true,
    manualColumnResize: true,
    contextMenuCopyPaste: {
        swfPath: '/bower_components/zeroclipboard/dist/ZeroClipboard.swf'
    },
    copyPaste: true,
    mergeCells: true,
    search: true,
    stretchH: 'all',
    autoColumnSize: {useHeaders: true},
    autoRowSize: {syncLimit: 300},
    width: 1000,
    height: window.innerHeight - 100,
    licenseKey: "xxxxx-xxxxx-xxxxx-xxxxx-xxxxx"
};

Menu looks like this.

Question 1:

Is there any way to add custom item with all the default menu items? If so, I don't need answers to Question 3 and Question 4.

Question 2:

The most important part that let me ask this question is custom menu, that is "set_color". After clicking "Black" or "Red", it turns into that color, but after I change value of a cell, it turns back. How can I prevent the cells from turning their background color back?

Questions 3:

I want additional custom item besides all feature enabled. But I can't find proper key for "Merge" item. The current "Merge" function works so strangely. How to make the function works correctly?

Question 4:

I tried https://github.com/handsontable/handsontable/issues/2853 to implement paste functionality, but I see this error.

Uncaught TypeError: Cannot read property 'triggerPaste' of undefined

Please help me with those handsontable usage. Thanks in advance.

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