it's a new feature - I'd suggest to wait a bit before using it. I see that it's possible to get the attachment from the user and use it in the message, see:
You can try to use Power Automate flow with a File output parameter. That could also work as an input argument. I've used this expression to get the user attachment:
First(System.Activity.Attachments).Value
In case of any other questions, let me know. If the answer helped you, mark it, so that others can benefit from it.
Thank you for your reply! To ensure a great experience for everyone, your content is awaiting approval by our Community Managers. Please check back later.