Is it better to disenchant a golden legendary before or after the card is turned to wild? I know how the dust works on regular cards but I don’t remember reading how it works on Golden ones

If I have a golden legendary card that is going to go away soon, is it better to disenchant it now or wait ? I know how the dust works with regular cards, just not legendary ones.

If I have a Golden Legendary Malkorok, would it be better to disenchant him now or wait till the new expansion comes out ? I know how the dust works on regular cards but not on Golden ones…