When applying a read marker to a reply, prioritise the original sender's read marker above others.

[Half-Shot]

Your use case

What would you like to do?

When trying to determine if someone has read my message in a busy room, it can be helpful to see if their read marker is present which can become obscured with lots of markers from different members. The same logic applies to mentions too, I suppose.

Why would you like to do it?

It aids clarity on whether someone has read the message.

How would you like to achieve it?

Sort mentioned users above regular users.

Have you considered any alternatives?

No

Additional context

No response

Are you willing to provide a PR?

Possibly for Web, I'm afraid my android/ios abilities are not up to scratch.