Add row and col scope to table headers in TablePress

functions.php

/**
 * Add scope attributes to table headers
 *
 * @param  mixed $output HTML output of the table.
 * @param  mixed $table Table object.
 * @param  array $render_options Render options.
 * @return string HTML output of the table.
 */
function tablepress_add_scope( $output, $table, $render_options ) {
	$dom = new DOMDocument();
	$dom->loadHTML( $output );
	$xpath = new DOMXPath( $dom );
	if ( $render_options['table_head'] ) {
		$th = $xpath->query( '//thead/tr/th' );
		foreach ( $th as $node ) {
			$node->setAttribute( 'scope', 'col' );
		}
	}
	if ( $render_options['first_column_th'] ) {
		$th = $xpath->query( '//tbody/tr/th' );
		foreach ( $th as $node ) {
			$node->setAttribute( 'scope', 'row' );
		}
	}
	$output = $dom->saveHTML();
	return $output;
}
add_filter( 'tablepress_table_output', 'tablepress_add_scope', 10, 3 );