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Html elements iframe, command, and base

iframe element Defines an inline frame (ie a frame embedded in a document), command element The command element represents a command which the user can invoke, base element Specifies a base URL for all of the relative URLs in the document to use. These elements allows child elements from interactive, embedded, heading, sectioning, phrasing, and metadata content categories.

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iframe iframe and command, iframe, command, and base

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