title: Warning: Failed prop type: Invalid prop `value` supplied to `ForwardRef(Slider)`
body: <p>I am trying to create a Material UI range Slider which has two values on it. It works if I set:</p>
  <pre><code>const [value, setValue] = React.useState([5,20]);
     const [value, setValue] = React.useState([val]);
     const handleChange = (event, newValue) =&gt; {
         setValue(newValue);
    };
  
    return (
      &lt;div className={classes.root}&gt;
        &lt;Typography id=&quot;range-slider&quot; gutterBottom&gt;
          Temperature range
        &lt;/Typography&gt;
        &lt;Slider
          value={value}
          onChange={handleChange}
          valueLabelDisplay=&quot;auto&quot;
          aria-labelledby=&quot;range-slider&quot;
          getAriaValueText={valuetext}
        /&gt;
        &lt;Input value={value} /&gt;
      &lt;/div&gt;
    );
  </code></pre>
  <p>But if I set a value and assign that to the useState constant like this, it doesn't work. Even with the error, I don't understand why:</p>
  <pre><code>var val = [5,20]
  const [value, setValue] = React.useState([val])
  </code></pre>
  <p>I get this error:</p>
  <pre><code>Warning: Failed prop type: Invalid prop `value` supplied to `ForwardRef(Slider)`.
      in ForwardRef(Slider) (created by WithStyles(ForwardRef(Slider)))
  
      in WithStyles(ForwardRef(Slider)) (at demo.js:32)
  
      in div (at demo.js:28)
  
      in RangeSlider (at index.js:6)
  </code></pre>
  <p>The slider still renders but just with 1 point instead of 2 on it</p>