"Something went wrong!" after clickling on the icon to close the new thread view

[hagenest]

Steps to reproduce

1. Trying out the (great btw) new thread function
2. Click on the icon to close the thread view
3. "Something went wrong!" page appears instead
4. Clearing the cache and reloading doesn't make the room accesible again. Other rooms are still working though.

Outcome

What did you expect?

That the thread view closes but the rest of the conversation stays accessible

What happened instead?

Operating system

macOS 12.3

Application version

Version 1.10.9

How did you install the app?

homebrew

Homeserver

Synapse 1.41.1

Will you send logs?

Yes

[robintown]

See #21762, you should be using a more recent version of Synapse, but we will be releasing a hotfix for this soon.