Selectors

<h2>Earth</h2>
<p>
  Earth is the third planet from the Sun and the only astronomical object known to harbor life. This is enabled by Earth being a water world, the only one in the Solar System sustaining liquid surface water.
</p>

<h2 id="heading">Earth</h2>
<p>
  Earth is the third planet from the Sun and the only astronomical object known to harbor life. This is enabled by Earth being a water world, the only one in the Solar System sustaining liquid surface water.
</p>

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