Html elements mark, iframe, and keygen

mark element The HTML Mark Element (<mark>) represents highlighted text, i, iframe element Defines an inline frame (ie a frame embedded in a document), keygen element The HTML keygen element exists to facilitate generation of key material, and submission of the public key as part of an HTML form. These elements allows child elements from interactive, embedded, heading, sectioning, phrasing, and metadata content categories.

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mark mark and iframe, mark, iframe, and keygen

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