gist/matrix/m.room.tombstone

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- [On Matrix tombstones](#on-matrix-tombstones)
  - [PL50 tombstoning](#pl50-tombstoning)

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# On Matrix tombstones

```json
{
  "body": "This room has been replaced",
  "replacement_room": "!NewRoomID:example.net"
}
```

Note
[my scripts for tombstoning](https://gitea.blesmrt.net/mikaela/scripts/src/branch/master/bash),
`matrix-{tombstone,upgrade}-room.bash`.

## PL50 tombstoning

Synapse versions before
[1.11.0 (2020-02-21), technically 1.11.0rc1 (2020-02-19)](https://github.com/matrix-org/synapse/releases/tag/v1.11.0)
allowed power level 50 to set tombstones and thus hijack rooms. Thus this is
dependent on the Synapse version used at the time of room creation.

- [PR](https://github.com/matrix-org/synapse/pull/6834)
- [commit](https://github.com/matrix-org/synapse/commit/3404ad289b1d2e5bc5c7f277f519b9698dbdaa15)

In the same context invites were changed to require PL50 by default, and ACL
also got the requirement for PL100.