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#foreach ($att in $issue.lastcomment.attachments)
   $jirassimo.includeAttachment($att.id) 
#end

Attaching files added during workflow transition

In Jira you can configure your workflow transition in such a way that user will be asked to provide a comment when transiting the ticket. Here's an Atlassian article explaining how to do that: https://confluence.atlassian.com/jirakb/how-to-add-a-comment-during-a-transition-779160682.html

But you can also add a file upload functionality there, so, the user can upload a new file together with comment when executing a transition. This file is not a part of the last comment and if you want to send it via email, then use the following code snippet

#foreach ($item in $issue.last_change.items) 
  #if ($item.fieldId == "attachment")
    $jirassimo.includeAttachment($item.to)
  #end
#end

Attaching ALL files that are uploaded to specific ticket

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