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If you have attachments on an issue and you try to export a template with extension DOCX, you will be able to see, at the end of the file, the attachments included in the document generated. To open an attachment, you just need to do double-click on the attachment icon, see the examples below.
If you have attachments on an issue and you try to export a template with an extension PDF, you will able to see the symbol 
in the left sidebar in the Adobe Acrobat Reader, the attachments included in the document generated. To open an attachment, you just need to do double-click on the attachment icon, see the examples below.
As you can see, this is very simple to do and allows you to get attachments included in your template.
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