title: canvas fill text changed when hovering over chartjs tooltips
body: <p>Chart after initial load.</p>
  
  <p><a href="https://i.stack.imgur.com/E2jv6.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/E2jv6.png" alt="enter image description here"></a></p>
  
  <p>Hovering over chart.js tooltips.</p>
  
  <p><a href="https://i.stack.imgur.com/mfRKG.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/mfRKG.png" alt="enter image description here"></a></p>
  
  <p>Here is the code I am using to add the text on the canvas.</p>
  
  <pre><code>plugins: [{
    afterDraw: function (chart) {
      let text = '0.9712'
      let textX = 464
      let textY = 85
      chart.ctx.fillStyle = '#36a2eb'
      chart.ctx.fillRect(textX - 10, textY - 13, 100, 17)
      chart.ctx.fillStyle = '#ffffff'
      chart.ctx.fillText(text, textX, textY)
    }
  }]
  </code></pre>
  
  <p>What causes this?</p>