The Highlight feature marks a part of the text that is relevant in another context.
The <mark>
element MUST be used to represent the Highglight feature as it is intended to mark parts of content that are relevant in another contexts[1].
Example:
<p>Find results:</p>
<p>Your <mark>code</mark> is beautiful.</p>
Highlight feature MAY be used as a mechanism to mark content in the editor found by “Find” or similar feature.