SQLSTATE[42000]: Syntax error or access violation

I get a wsod on installing regcode. The log says:

Drupal\Core\Database\DatabaseExceptionWrapper: SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes: CREATE TABLE {regcode} ( `rid` INT unsigned NOT NULL auto_increment COMMENT 'RID', `uid` INT unsigned NULL DEFAULT NULL COMMENT 'User ID', `created` INT NULL DEFAULT NULL COMMENT 'Code creation time', `lastused` INT NULL DEFAULT NULL COMMENT 'Code last used time', `begins` INT NULL DEFAULT NULL COMMENT 'Code activation date', `expires` INT NULL DEFAULT NULL COMMENT 'Code expiry date', `code` VARCHAR(255) NOT NULL DEFAULT '' COMMENT 'The registration code', `is_active` INT unsigned NOT NULL DEFAULT 1 COMMENT 'Whether the code is active', `maxuses` INT unsigned NOT NULL DEFAULT 1 COMMENT 'Maximum times a code can be used', `uses` INT unsigned NOT NULL DEFAULT 0 COMMENT 'Number of times the code has been used', PRIMARY KEY (`rid`), UNIQUE KEY `code` (`code`) ) ENGINE = InnoDB DEFAULT CHARACTER SET utf8mb4 COMMENT 'Hold registration codes'; Array ( ) in drupal_install_schema() (line 122 of /var/www/profile.myclimateservices.eu/web/core/includes/schema.inc).

Set to critical since the module is not useable with that