Describe the bug

The rich text editors allow for graphics to be inserted into custom registration emails, but those graphics do not appear to be in the email to participants, neither in an embedded nor linked format.

To Reproduce

1. In a meeting component, configure a custom registration email with an inserted graphic
2. Have a participant register for the meeting
3. Registration email does not include the graphic

Expected behavior

For the graphic to appear in the email sent to participants registering for the meeting.

Screenshots

Configured registration email

Received registration email

Stacktrace

No response

Extra data

Tested in both v.27 on Green Party of Canada and on a v.28.1 development server.

Additional context

No response