Timeline in room has "reverted" to a few days ago.

[Half-Shot]

Steps to reproduce

1. I open a particular room, it's a standard encrypted group chat. It's been okay until today.
2. The room timeline is stuck at a certain point, and sending messages causes them to send but then not be visible. Verifying from other clients, the timeline looks normal.

I can scroll up to previous messages but I can't scroll past a certain point.

Outcome

What did you expect?

The room timeline is up to date.

What happened instead?

The room timeline is not up to date.

Operating system

Arch Linux

Application version

Element version: 1.11.52 Crypto version: Olm 3.2.15

How did you install the app?

Package manager (pacman)

Homeserver

Synapse 1.92.2 (half-shot.uk)

Will you send logs?

Yes

[Half-Shot]

Further testing reveals the room is okay if I am linked to it via a permalink and I don't scroll up too far. If I scroll up enough, the client gets stuck and I can't scroll down again.