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    <title>stretchy rtl</title>
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    <math dir="rtl"><mo>&#x230a;</mo><mo>&#x2308;</mo><mo>{</mo><mo>[</mo><mo rspace="3em">(</mo><mspace width="1em" height="2em" depth="2em" mathbackground="red"/><mo lspace="2em">)</mo><mo>]</mo><mo>}</mo><mo>&#x2309;</mo><mo>&#x230b;</mo></math>

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