Read Receipts are sent even if a modal overlays the timeline

### Steps to reproduce

1. View a room
2. Open any modal, that will obstruct the room view (user settings, preferences, room settings, ...)
3. Wait for a new message to be received

### What happened?

The read receipt is sent directly and the notification count is decremented

### What did you expect?

For the notification count to remain the same and the read receipts to not be sent until the modal is closed and I can actually lay my eyes on the event

### Operating system

_No response_

### Browser information

_No response_

### URL for webapp

app.element.io

### Have you submitted a rageshake?

No