Hi,
this module is located in modules/Utils/Attachment...
Take a look into:
- remote.js - there is a JS function that calls create_remote.php,
- create_remote.php - generates database entry,
- Attachment_0.php, line 339 - adds button to lightbox
The easiest way is to add another buttons - add argument to JS function and pass it to create_remote...
We welcome patches 🙂
Paul