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  to you under the Apache License, Version 2.0 (the
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<#assign markupOutput1="<b>Test</b>"?no_esc>
<#assign markupOutput2="Foo & bar"?esc>

As expected:
${markupOutput1}
${markupOutput2}

Double escaping:
${markupOutput1?markup_string}
${markupOutput2?markup_string}