Toolbox Filter Example - Highlight WYSIWYG with settings

toolbox_example_highlight_with_settings.php

<?php

add_filter( 'toolbox/helpers/settings/type=wysiwyg' , 'more_wysiwyg_settings' , 10, 2 );

function more_wysiwyg_settings( $settings ) {

	return array_merge( $settings, array(
				'highlight' => array(
					'type'        => 'text',
					'label'       => __('Highlight Text', 'textdomain'),
				),
				'highlightcolor' => array(
				    'type'          => 'color',
				    'label'         => __( 'Highlight Color', 'textdomain' ),
				    'default'       => '333333',
				    'show_reset'    => true,
				),
	) );
}

add_filter( 'toolbox/helpers/get_acf_field/type=wysiwyg' , 'highlight_wysiwyg', 10, 5 );

function highlight_wysiwyg( $string, $field_object, $value, $atts, $postid ) {
	if (isset($atts['highlight']) && $atts['highlight'] !== ''):

			$regex = '/((?i)\b'.$atts['highlight'].'\b)/m';

			return preg_replace( $regex , '<span style="background-color:#'.$atts['highlightcolor'].';color:#fff;padding-left:5px;padding-right:5px;">'.'$1'.'</span>', $string);
	endif;
	return $string;
}