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<title>CSS4 media query test: prefers-contrast using matchMedia and addListener.</title>
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  <p>Initial value of query.matches: <span id="before">false</span> - should be false</p>
  <p>Updated value of query.matches: <span id="after">true</span> - should be true</p>
  <p>Note the updated value will only be filled if the listener fires.</p>
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