title: Tooltip callbacks in line chart JS not working
body: <p>I'm using line chart js to display a graph and I'm trying to calculate the difference between the selected point and the previous one and render it in a tool tip.</p>
  <p>I've read that I should use callbacks function but when I tried it nothing happen.</p>
  <p>Even I only try to change the tittle
  Here's my options for my line chart if anyone can help :)
  Chart js version : 3.6.1</p>
  <pre><code>  plugins: {
      legend: {
        display: false
      },
      title: {
        display: true,
        font: {
          size: 18,
        },
        color: &quot;white&quot;
      },
      zoom: {
        zoom: {
          drag: {
            enabled: true
          },
          mode: 'xy',
        }
      },
      tooltip: {
        callbacks: {
          title: function () {
            return &quot;my tittle&quot;;
           }
        }
      }
  }
  
  </code></pre>