wrong result when comparing utf8 column with an invalid literal

DROP DATABASE IF EXISTS `strict_unicode_test`;

SET NAMES 'utf8' COLLATE 'utf8_unicode_ci';

SET SESSION sql_mode='STRICT_ALL_TABLES';

CREATE DATABASE `strict_unicode_test` COLLATE utf8_unicode_ci;

USE `strict_unicode_test`;

SHOW VARIABLES LIKE 'coll%';

SHOW VARIABLES LIKE 'character%';

DROP TABLE IF EXISTS `users`;

CREATE TABLE `users` (

  `ID` bigint(20) unsigned NOT NULL AUTO_INCREMENT,

  `login` varchar(60) COLLATE utf8_unicode_ci NOT NULL DEFAULT '',

  PRIMARY KEY (`ID`)

) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;

INSERT INTO users (login) VALUES ('admin');

SELECT * FROM `users` WHERE `login` = 'admin��';

SHOW WARNINGS;