Chart.js overlapping tooltip text

Question

I have a chart.js line chart:

var myLineChart = new Chart(ctx, {
                type: 'line',
                data: lineChartData,
                options: {
                    tooltips: {
                        titleSpacing: 5,
                    },
                    responsive: true,
                    legend: {
                        display: false,
                    },
                    scales: {
                        yAxes: \[
                            {
                                gridLines: {
                                    color: '#354657',
                                },
                                ticks: {
                                    fontColor: '#fff',
                                    stepSize: 5,
                                },
                            },
                        \],
                        xAxes: \[
                            {
                                gridLines: {
                                    color: '#354657',
                                },
                                ticks: {
                                    fontColor: '#fff',
                                },
                            },
                        \],
                    },
                },]

The problem is, it renders tooltips with overlapping text, as shown:

This should show Current, 41.9. But they are overlapped. I tried changing titlespacing, but that didn't do anything. How can I fix this?

Answer 1

What I personally do for all my custom charts is create a custom title / label independent of what I pass as options to the chart. I like to have control over the HTML / whatever which gets outputted to the label. You can do this with the callbacks key

  tooltips: {
    enabled: true,
    position: "nearest",
    caretSize: 20,
    mode: "index",
    intersect: false,
    titleFontSize: 16,
    titleFontColor: "white",
    backgroundColor: COLORS.DARK,
    callbacks: {
      title: (tooltipItem, _) => {
        return formatDate("LT", tooltipItem[0].xLabel);
      },
      label: (tooltipItem, _) => {
        const { yLabel } = tooltipItem;
        return `${yLabel} Sessions Recorded`;
      }
    }
  },