Do NOT use Black Lion Vouchers if you have everything unlocked!

Title, kinda.

I wanted to test the functionality since there was an update:

Black Lion Vouchers will now only display options not owned by the player, preventing them from claiming something they already own.

Opening it gives you a tiny window with no selection and only an "Accept" button. Clicking that button will consume the voucher without giving you anything for it.

So if you already know that you got everything unlocked, do not use the vouchers! Just lost two like this because I didn't notice the first time.