ackduck/changelog.d/1747.feature.md

Implemented event rejection, which should resolve and prevent future netsplits of the kinds observed within some Continuwuity rooms. Also resolved several bugs related to both soft-failing events, and event backfilling, which should improve state resolution stability. The !admin debug get-pdu command was updated to disambiguate event acceptance status, and !admin debug show-auth-chain was added to visually display event auth chains, which may assist developers in debugging strangely complex events.

Contributed by @nex.