Wanderlust Unique boots not activating for any (all?) slows

Report reference number 2,186,309,141.

Wanderlust unique boots do not activate for many common debuffs that inflict (movement) slows, including some that would/do activate silver charms.

Reference number is for an example of the large spiders that inflict "Webbed: you are slowed" as a debuff in traitor's passage or titan's grotto.

Boots appear to work against slow from chill (e.g. against Geonor) but not against other slows from debuffs.