public function get_header_image_src() {
		$src = get_option( 'lifterlms_email_header_image', '' );
		if ( is_numeric( $src ) ) {
			$attachment = wp_get_attachment_image_src( $src, 'full' );
			$src        = $attachment ? $attachment[0] : '';
		}
		/**
		 * Filters the header image src
		 *
		 * @since 3.8.0
		 *
		 * @param string $src Image `src` attribute value.
		 */
		return apply_filters( 'llms_email_header_image_src', $src );
	}