Stuck unread messages

[non-Jedi]

Steps to reproduce

Related to #24392.

Not sure. Only having the issue in a single room. Tried pressing the "mark as read" button. Tried scrolling way up and back down to bottom. Tried sending a new message into the room. Still says I have 2 unread.

Also tried marking as read in fluffychat on my phone as well a other troubleshooting steps above. Flufflychat also shows unread messages but 5 instead of 2.

Outcome

What did you expect?

Reading to the bottom of a room should mean that notification number next to room disappears.

What happened instead?

Notification number indicating 2 unread messages and room stays bolded to indicate unread messages.

Operating system

WSL

Browser information

Firefox 115.0.2

URL for webapp

develop.element.io

Application version

Element version: d1f7b08-react-57a0d99dc851-js-3f7af189e410 Olm version: 3.2.14

Homeserver

matrix.thebeckmeyers.xyz synapse 1.89.0

Will you send logs?

Yes

[non-Jedi]

We have never used threading in this room which seems to be a common cause of similar issues.

[non-Jedi]

On further inspection, this is likely either a synapse bug or an issue with how workers are setup on my homeserver. Every single POST to send a read receipt is coming back with a 500 error right now regardless of which room it's for.

[non-Jedi]

Problem went away after removing the read receipt worker. Apologies for the noise.