diff --git a/changelogs/client_server/newsfragments/2125.feature b/changelogs/client_server/newsfragments/2125.feature
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+Add `/_matrix/client/v1/room_summary/{roomIdOrAlias}` and extend `/_matrix/client/v1/rooms/{roomId}/hierarchy` with the new optional properties `allowed_room_ids`, `encryption` and `room_version` as per [MSC3266](https://github.com/matrix-org/matrix-spec-proposals/pull/3266).
diff --git a/changelogs/server_server/newsfragments/2125.feature b/changelogs/server_server/newsfragments/2125.feature
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+Extend `/_matrix/federation/v1/hierarchy/{roomId}` with the new optional properties `encryption` and `room_version` as per [MSC3266](https://github.com/matrix-org/matrix-spec-proposals/pull/3266).