Your sealed lockets
These are the lockets sealed from this browser. The cancel token for each one is stored here and nowhere else, so a locket sealed on another device will not appear in this list.
Cancel using a saved card
If the record is gone from this device, the .cancelcard file saved when the locket was sealed still works.
Erase local data
This removes everything half-locket has stored in this browser, including every cancel token above. Lockets already sealed are unaffected, but they can no longer be cancelled from here unless you still hold their cards.