' . esc_html__( 'Note', 'business-center' ) . ':' . esc_html__( ' The recommended size for image is 1300px by 600px while using it for slider', 'business-center' ) . '

'; } elseif ( 'jetpack-testimonial' == get_post_type( $post_id ) ) { return $content .= '

' . esc_html__( 'Note', 'business-center' ) . ':' . esc_html__( ' The recommended size for image is 500px by 375px while using it for testimonial', 'business-center' ) . '

'; } return $content; } add_filter( 'admin_post_thumbnail_html', 'business_center_slider_image_instruction', 10, 2);