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you have to add on to the code.

the original is this

// Span
		'span'             => array(
			'class'     => true,
		),

you would have to edit it like this

// Span
		'span'             => array(
			'class'     => true,
                        'style'     => true,
		),

and probably the same thing for the paragraph tag ‘p’ , but for this you will need to just add it on like this.

// Paragraph
		'p'          => array(
			'dir'    => true,
			'style'     => true,
		),

basically any child elements of the tag add it in the function.