- Add an option to enable encryption by default for new rooms. ([\#7639](https://github.com/matrix-org/synapse/issues/7639))
- Add support for running multiple media repository workers. See [docs/workers.md](https://github.com/matrix-org/synapse/blob/develop/docs/workers.md) for instructions. ([\#7706](https://github.com/matrix-org/synapse/issues/7706))
- Add support for running multiple media repository workers. See [docs/workers.md](https://github.com/matrix-org/synapse/blob/release-v1.16.0/docs/workers.md) for instructions. ([\#7706](https://github.com/matrix-org/synapse/issues/7706))
- Media can now be marked as safe from quarantined. ([\#7718](https://github.com/matrix-org/synapse/issues/7718))
- Expand the configuration options for auto-join rooms. ([\#7763](https://github.com/matrix-org/synapse/issues/7763))