Hey all,

Matrix 1.6 is out there! Like Matrix 1.5 back in November, this release is largely a maintenance update. Matrix 1.1 through 1.4 have been relatively major upgrades, so a little time between features doesn’t feel like a bad idea :)

As with all spec releases, we encourage implementations to gradually update over the next few months rather than have support for everything on release day - please be kind to the projects you use, and help them gain support if able.

Matrix 1.6 sees just 7 MSCs get merged, though this is to be expected from a maintenance release. Check out Matthew’s Matrix 2.0 talk at FOSDEM for an idea of what’s expected over the next few releases.

We’ve covered a couple of the MSCs below, but read on to the full changelog for the full picture.

MSC3030: Jump to date API

_It’s here! The time machine we’ve been waiting for! _

Primarily part of the Gitter feature parity project (congratulations to the team going all-in on Matrix, by the way) to drive the Matrix Public Archive, the new API gives clients the ability to jump back in time to a nearby event. Being able to find something that was posted on a given day/week, but not being sure of which keywords to look for is a major usability improvement - many thanks to the Gitter team for making Matrix better!

MSC3706: Faster joins (part 1)

Matrix is going voom

Synapse 1.76 enabled faster joins by default, and while there’s a lot of Python going into making joins as fast as possible, the specification side is a relatively small change at the moment: just don’t send as many events during joins (omit_members).

There’s potentially more work on the horizon for making faster joins even faster and more robust, and some of that might involve spec work: keep an eye on Synapse releases and TWIM for updates as we make our way to faster joins in Matrix 2.0 :)

The full changelog

MSCs are how the spec changes in the way it does - adding, fixing, and maintaining features for the whole ecosystem to use. Check out the full changelog below, and the Spec Change Proposals page for more information on how these MSCs got merged (hint: they submitted a proposal, which anyone can do - take a look at the Matrix Live episode where Matthew covers the proposal process).

Client-Server API

Backwards Compatible Changes

  • Add information on standard error responses for unknown endpoints/methods, as per MSC3743. (#1347)
  • Add /rooms/<roomID>/timestamp_to_event endpoint, as per MSC3030. (#1366)
  • Define hkdf-hmac-sha256.v2 MAC method for SAS verification, as per MSC3783. (#1412)

Spec Clarifications

  • Clarify the power levels integer range. (#1169, #1355)
  • Clarify that /context always returns event even if limit is zero. Contributed by @sumnerevans at @beeper. (#1239)
  • Clarify what fields are required when deleting a pusher (#1321)
  • Improve the presentation of push rule kinds and actions. (#1348)
  • Add missing description to m.call.answer schema. (#1353)
  • Fix various typos throughout the specification. (#1363)
  • Clarify parts of the end-to-end encryption sections. (#1381)
  • Move login API definitions to the right heading. Contributed by @HarHarLinks. (#1382)
  • Clarify which events will be included in Stripped State. Contributed by @andybalaam. (#1409)
  • Add links to the spec for the definition of 3PID medium. (#1417)
  • Correct the order of the default override pushrules in the spec. (#1421)
  • Improve distinction between tags and their attributes in the rich text section. Contributed by Nico. (#1433)

Server-Server API

Breaking Changes

  • Remove keyId from the server /keys endpoints, as per MSC3938. (#1350)

Backwards Compatible Changes

  • Add information on standard error responses for unknown endpoints/methods, as per MSC3743. (#1347)
  • Add /timestamp_to_event/<roomID> endpoint, as per MSC3030. (#1366)
  • Extend /_matrix/federation/v2/send_join to allow omitting membership events, per MSC3706. (#1393, #1398)
  • Note that /_matrix/federation/v2/send_join should include heroes for nameless rooms, even when allowed to omit membership events, per MSC3943. (#1425)

Spec Clarifications

  • Include examples inline instead of using a reference for invite endpoint definitions. (#1349)
  • Fix POST _matrix/federation/v1/user/keys/claim response schema. (#1351)
  • Correct the default invite level definition in the "Checks performed on receipt of a PDU" section. (#1371)
  • Clarify that CNAMEs are permissible for server names. (#1376)
  • Fix edu_type in EDU examples. (#1383)

Application Service API

Backwards Compatible Changes

  • Add information on standard error responses for unknown endpoints/methods, as per MSC3743. (#1347)

Identity Service API

Backwards Compatible Changes

  • Add information on standard error responses for unknown endpoints/methods, as per MSC3743. (#1347)

Push Gateway API

Backwards Compatible Changes

  • Add information on standard error responses for unknown endpoints/methods, as per MSC3743. (#1347)

Room Versions

Backwards Compatible Changes

  • Update the default room version to 10, as per MSC3904. (#1397)

Spec Clarifications

  • Clarify the grammar for room versions. (#1422)
  • Fix various typos throughout the specification. (#1423)

Appendices

No significant changes.

Internal Changes/Tooling

Spec Clarifications

  • Add link to the unstable spec to the README. (#1357)
  • Improve safety of the proposals retrieval script in the event of failure. (#1368)
  • Rename <content> to content in the OpenAPI files for content uploads. (#1370)
  • Stop autogenerating examples where we already have an example. (#1384)
  • Improve formatting of definitions in the Push Notifications section. (#1415)