remove_action( 'wpcf7_init', 'wpcf7_add_form_tag_submit', 10, 0 );
add_action( 'wpcf7_init', 'shw_custom_submit_cf7', 10, 0 );

function shw_custom_submit_cf7() {
	wpcf7_add_form_tag( 'submit', 'shw_custom_submit_cf7_handlers' );
}

function shw_custom_submit_cf7_handlers( $tag ) {
	$class = wpcf7_form_controls_class( $tag->type, 'has-spinner' );

	$atts = array();

	$atts['class'] = $tag->get_class_option( $class );
	$atts['id'] = $tag->get_id_option();
	$atts['tabindex'] = $tag->get_option( 'tabindex', 'signed_int', true );

	$value = isset( $tag->values[0] ) ? $tag->values[0] : '';

	// if ( empty( $value ) ) {
	// 	$value = __( 'Send', 'contact-form-7' );
	// }

	$atts['type'] = 'submit';
	//$atts['value'] = $value;

	$atts = wpcf7_format_atts( $atts );

	$html = sprintf( '<button type="submit" %1$s class="wpcf7-form-control has-spinner wpcf7-submit">'.html_entity_decode($value).'</button>', $atts );

	return $html;
}