public static function get_non_en_accepted_wp_locales_from_header() {
		$res = array();

		$http_locales = self::get_http_locales();

		if ( empty( $http_locales ) ) {
			return $res;
		}

		if ( is_array( $http_locales ) ) {
			foreach ( $http_locales as $http_locale ) {
				$http_locale = explode( '-', $http_locale );

				$lang   = $http_locale[0];
				$region = ! empty( $http_locale[1] ) ? $http_locale[1] : null;

				if ( is_null( $region ) ) {
					$region = $lang;
				}

				/*
				 * Discard English -- it's the default for all browsers,
				 * ergo not very reliable information
				 */
				if ( 'en' === $lang ) {
					continue;
				}

				// Region should be uppercase.
				$region = strtoupper( $region );

				$mapped = self::map_locale( $lang, $region );

				if ( $mapped ) {
					$res[] = $mapped;
				}
			}

			$res = array_unique( $res );
		}

		return $res;
	}