---
$schema: https://json-schema.org/draft/2020-12/schema

allOf:
  - $ref: core-event-schema/state_event.yaml
description: |-
    A topic is a short message detailing what is currently being discussed
    in the room.  It can also be used as a way to display extra information
    about the room, which may not be suitable for the room name. The room
    topic can also be set when creating a room using
    [`/createRoom`](client-server-api/#post_matrixclientv3createroom), either
    with the `topic` key or by specifying a full event in `initial_state`.
  
    If the `topic` property is absent, null, or empty then the topic is unset. In other words,
    an empty `topic` property effectively resets the room to having no topic.

    In order to prevent formatting abuse in room topics, clients SHOULD
    limit the length of topics during both entry and display, for instance,
    by capping the number of displayed lines. Additionally, clients SHOULD
    ignore things like headings and enumerations (or format them as regular
    text).
properties:
  content:
    properties:
      topic:
        description: |-
          The topic in plain text.

          This SHOULD duplicate the content of the `text/plain`
          representation in `m.topic` if any exists.
        type: string
      m.topic:
        type: object
        title: TopicContentBlock
        x-addedInMatrixVersion: "1.15"
        description: |-
          Textual representation of the room topic in different mimetypes.
        properties:
          m.text:
            $ref: components/m_text_content_block.yaml
    required:
      - topic
    type: object
  state_key:
    description: A zero-length string.
    pattern: '^$'
    type: string
  type:
    enum:
      - m.room.topic
    type: string
title: Topic
type: object