When editing a message containing ---- (<hr />) markdown, those ----'s are lost

[benparsons]

Steps to reproduce

1. Create a message containing "----"
2. edit the message
3. notice that the "----" is missing in the edit field

Outcome

What did you expect?

Keep the markdown I entered

What happened instead?

----'s were lost

Operating system

macOS

Browser information

Chrome 96

URL for webapp

app.element.io

Application version

Element version: 1.9.8

Homeserver

element.io

Will you send logs?

No