JSFiddle - React, Tailwind, and code Playground

HTML

<div id="chartCustomMarkers"></div>

JavaScript

require(["dojox/charting/themes/Claro", "dojox/charting/Chart", "dojox/charting/axis2d/Default", "dojox/charting/plot2d/Lines", "dojox/charting/SimpleTheme",
        "dojox/charting/plot2d/MarkersOnly"],
        function(claro, Chart, Default, Lines, SimpleTheme, MarkersOnly){
            var customTheme = new SimpleTheme({
                    markers: {
                        DIAMOND: "m0,-3 l3,3 -3,3 -3,-3 z",
                        CROSS:        "m0,-3 l0,6 m-3,-3 l6,0"
                    }
                });
                
                var chart = new Chart("chartCustomMarkers",
                    {
                        title: "Line Chart",
                        titlePos: "top",
                        titleFont: "normal normal normal 15pt Arial",
                    });
                chart.addPlot("default", { type: MarkersOnly })
                //chart.addPlot("default", { type: Lines })
                    .addAxis("x")
                    .addAxis("y", { vertical: true })
                    .addSeries("Series 1", [1, 2, 2, 3, 4, 5, 5, 7])
                    .addSeries("Series 2", [2, 5, 4, 8, 5, 6, 6, 1])
                    //.setTheme(claro)
                    .setTheme(customTheme)
                    .render();
        });