Pinned messages release announcement (web)

[daniellekirkwood]

Your use case

We're releasing pinned messages in the RC this week and would like to have a release announcement to go with it. There's a draft PR already but it needs closing off I think with updated copy...

Reference : https://github.com/element-hq/element-internal/issues/624

Have you considered any alternatives?

No response

Additional context

No response