Anyone can see it. Because the item is public, it can also be found by keyword search.
It’s shown automatically to people you’ve matched with. It isn’t shown to anyone else.
Only when you’ve matched and both of you have set the same item to “mutual item reveal” does that item become visible to both of you at the same time. There’s no request or approval. If either of you changes the setting, the other person automatically stops seeing it too, so it stays private.
When someone sends a [Request] for your item and you approve it, that item becomes visible to both of you at the same time. Even with approval, you can’t see someone’s item while you aren’t showing them the same item of yours. After approving, you can still close it person by person (“🛡️ Shield Center” → “🔐 Reveal management”).
No one can see it, and it doesn’t match keyword searches. It stays anonymous but is still used for the system’s matching (its contents are never shown to anyone).
A photo reveal opens for both of you at the moment the other person accepts. Even if the other person closes it before you’ve looked, you can still view it once within 72 hours.