Join the waitlist and you are emailed the moment it is back — and the creator can see the demand.
A sold-out listing shows a waitlist. Join it and you are told as soon as it is back in stock.
You do not need an account
An email address is enough.
What you get
One notice, with the number back in stock, linking straight to the item. Everyone waiting is told at once and only a few can buy, so the link goes to the listing rather than making you hunt for it.
The creator sees the demand
The number of people waiting shows on the creator's own screen. That is often what makes a restock happen at all — without it, a sold-out listing simply looks like a finished one.
Leaving the list
There is a link in the email. If you have an account you can also leave from the listing itself.
If it sells out again
You can rejoin. Being notified once does not remove you permanently.