ilters( 'autoptimize_filter_meta_optim_nonbool', array( 'ao_post_preload' ) ) ) ) {
                // but make sure to return false for text input.
                return false;
            }
            return true;
        } else if ( array_key_exists( 'ao_post_optimize', $_meta_value ) && 'on' !== $_meta_value['ao_post_optimize'] ) {
            // ao entirely off for this page.
            return false;
        } else if ( in_array( $optim, apply_filters( 'autoptimize_filter_meta_optim_with_filters', array() ) ) ) {
            // if an $optim is registered as having a filter, apply filter and return that (default false).
            return apply_filters( 'autoptimize_filter_meta_filtered_optim', false, $optim, $_meta_value );
        } else if ( array_key_exists( $optim, $_meta_value ) && empty( $_meta_value[ $optim ] ) ) {
            // sub-optimization off for this page.
            return false;
        } else if ( array_key_exists( $optim, $_meta_value ) && 'on' === $_meta_value[ $optim ] ) {
            // sub-optimization is explictly on.
            return true;
        } else if ( array_key_exists( $optim, $_meta_value ) && in_array( $optim, array( 'ao_post_preload' ) ) && ! empty( $_meta_value[ $optim ] ) ) {
            // a non-bool metabox optimization (currently only preload field), return value instead of bool.
            return $_meta_value[ $optim ];
        } else if ( in_array( $optim, array( 'ao_post_preload' ) ) && ( ! array_key_exists( $optim, $_meta_value ) || empty( $_meta_value[ $optim ] ) ) ) {
            // a non-bool metabox optimization not found or empty, so returning false.
            return false;
        } else {
            // when in doubt "go" for optimization, but this should never happen?
            if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
                error_log( 'AO meta box logic fallback; well, how did I get here? Maybe this helps: looking for ' . $optim . ' in ' . json_encode( $_meta_value ) );
            }
            return true;
        }
    }

    /**
     * Are the post meta AO settings active (default: no)?
     *
     * @return bool
     */
    public static function is_ao_meta_settings_active() {
        static $_meta_settings_active = null;

        if ( null === $_meta_settings_active ) {
            $_meta_settings_active = apply_filters( 'autoptimize_filter_enable_meta_ao_settings', autoptimizeOptionWrapper::get_option( 'autoptimize_enable_meta_ao_settings', '1' ) );
        }

        return $_meta_settings_active;
    }
}