Setting the "feather cooldown" config to a value higher than when it was when a PlayerFeathers Object was created disables regeneration for that Player, requiring The reinstancing of the Player entity (relog) to reenable the regeneration.
This is due to the maxcooldown field only being set on the creation of the Object, causing the addCooldown method to cap the cooldown to the old max value and thus never reaching the new config value.