Pretty simple, when you use withdraw with the hunter perk that gives it a 300 dam bubble for 2 secs, it does it instantly. Making u no longer invisible showing the bubble and also wasting it. Please make the bubble appeare after comming out of withdraw
This is currently working as intended.
Of note, when the shield is applied, enemy players cannot see the Shield (though you can). You are still invisible for the expected period after using the Withdraw ability.