Overview

This section covers the message content types that render inside the main message body: attachments, previews, file UI, media galleries, and rich content fallbacks.

Use This Group When

You want to customize how attachments render.
You need to change file, gallery, video, or audio presentation.
You want to override rich link previews or unsupported attachment fallbacks.

Start with `Attachment`

Attachment is the main entry point for attachment rendering inside the message body. If your product needs custom attachment dispatch or custom attachment types, start there.