Issue Summary

An MP3/MP4 file, when added as an inline attachment using a 'Card' option, doesn't show up as an MP3/MP4 file and instead shows just as text and throws an error instead of displaying the actual file:

Steps to Reproduce

1. Click reply to customer, add attachment and select option 'card'
   
2. Click save
3. Open the notification received by any recipient and check for the attached MP3/MP4 file

Expected Results

The attached file should be shown as a link which can be opened to view or download.

Actual Results

The attached file is shown as just text (not clickable)

Workaround

Currently, the workaround is to select the inline option while attaching the MP3/MP4 file.