Previous: Store custom flags and keywords, Up: The Gnus Registry
The registry has a simple API that uses a Message-ID as the key to store arbitrary data (as long as it can be converted to a list for storage).
If any extra entries are precious, their presence will make the registry keep the whole entry forever, even if there are no groups for the Message-ID and if the size limit of the registry is reached. By default this is just
(marks)so the custom registry marks are precious.