nodered_cfg/node_modules/node-red-dashboard/nodes/ui_spacer.html

<script type="text/javascript">
    RED.nodes.registerType('ui_spacer', {
        category: 'config',
        color: '#D4F0F8',
        defaults: {
            name: {value: "spacer"},
            group: {type: 'ui_group', required:true},
            order: {value: 0},
            width: {value: 0, validate: function(v) {
                    var width = v||0;
                    var currentGroup = $('#node-input-group').val()||this.group;
                    var groupNode = RED.nodes.node(currentGroup);
                    var valid = !groupNode || +width <= +groupNode.width;
                    $("#node-input-size").toggleClass("input-error",!valid);
                    return valid;
                }
            },
            height: {value: 0},
            className: {value: ''}
        },
        z: RED.workspaces.active(),
        inputs:0,
        outputs:0,
        hasUsers: false,
        icon: "ui_spacer.png",
        paletteLabel: 'spacer',
        label: function() { return this.name + " " + this.width + "x" + this.height; },
        labelStyle: function() { return this.name?"node_label_italic":""; },
        oneditprepare: function() {
            $("#node-input-size").elementSizer({
                width: "#node-input-width",
                height: "#node-input-height",
                group: "#node-input-group"
            });
        },
        oneditsave: function() {
            this.width = $("#node-input-width").val();
            this.height = $("#node-input-height").val();
        }
    });
</script>

<script type="text/html" data-template-name="ui_spacer">
    <div class="form-row">
        <label for="node-input-group"><i class="fa fa-table"></i> Group</label>
        <input type="text" id="node-input-group">
    </div>
    <div class="form-row">
        <label><i class="fa fa-object-group"></i> Size</label>
        <input type="hidden" id="node-input-width">
        <input type="hidden" id="node-input-height">
        <button class="editor-button" id="node-input-size"></button>
    </div>
    <div class="form-row">
        <label for="node-input-className"><i class="fa fa-code"></i>  Class</label>
        <input type="text" id="node-input-className" placeholder="Optional CSS class name(s) for widget"/>
    </div>
</script>