`pendedkeyvalue`.`value` still too narrow

I came across the very same bug that was already reported in #301 (closed). This bug should have been fixed by !225 (merged) as it seems for me. I am running GNU Mailman 3.2.0a1 (La Villa Strangiato) (rev 324226f1, latest master from gitlab). You can find the full trace in trace.log

The table pendedkeyvalue was created as:

CREATE TABLE `pendedkeyvalue` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `key` varchar(255) CHARACTER SET utf8 COLLATE utf8_bin DEFAULT NULL,
  `value` varchar(510) DEFAULT NULL,
  `pended_id` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `ix_pendedkeyvalue_pended_id` (`pended_id`),
  KEY `ix_pendedkeyvalue_value` (`value`),
  KEY `ix_pendedkeyvalue_key` (`key`),
  CONSTRAINT `pendedkeyvalue_ibfk_1` FOREIGN KEY (`pended_id`) REFERENCES `pended` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=35 DEFAULT CHARSET=latin1

After altering value manually to be of type varchar(1000) seems to resolve the issues for now but is not the proper fix for this. Any suggestions?