Mastodon 4.5 RC1 adds quote post authoring, async reply fetching & HTTP message signatures

Mastodon 4.5 Release Candidate 1 introduces several updates targeting client application developers and instance maintainers. The release highlights enhanced support for consent-respecting quote posts: new states such as blocked_account, blocked_domain, and muted_account now indicate when a quote should be hidden by default, even if technically permitted. Additionally, users can create quote posts directly through the REST API by supplying a quoted_status_id when posting.

Building on prior server capabilities, Mastodon 4.5 now enables the fetching of missing replies to remote statuses by default. The web user interface includes new behaviors to surface these replies, making remote conversation threads more complete for participants.

Following experimental trials in version 4.4, HTTP Message Signature support is now permanently enabled by default for servers running Mastodon 4.5 and later. This means incoming HTTP messages that include verifiable signatures are fully accepted, simplifying federation and improving protocol compliance for server administrators.