How to notify with attachments

I want to send attachments in a notification to a user. I’ve read about the
NotifyWithAttachment ScripAction in but it’s old
and refers to RT 2 not RT3. Is that still the way to do it or is there now
an alternative?

If so then how do I install it? And then how do I use it?

I understand how to create a template and a scrip. Would the template have
to have something in it like {$Transaction->Content()->Attachment} (just
making that up)?

Any advice appreciated.