Steps to reproduce

1. Open an email containing pictures.
2. Forward the email to yourself.
3. In the editor you can see the pictures.
4. Send the email.
5. Wait until you receive the email.
6. Open the email you just received.

Expected behavior

The email contains text and pictures.

Actual behavior

The email contains only the text of the forwarded email, while the pictures are missing.

Mail app version

2.2.5

Mailserver or service

IMAP/SMTP

Operating system

Ubuntu 18.04

PHP engine version

PHP 8.1

Web server

Apache (supported)

Database

MariaDB

Additional info

I also tested answering emails with embedded pictures as well by choosing "Edit as new message" and the result was the same. In the message editor, the images were there, while the received email didn't contain any images.