Identify File Name Format of PDF Attachments on Email

When emailing Transaction in PDF format, attachment shows file in Invoice_xx_xxxxxxxxxx.pdf format.

Steps to Reproduce:

I. Set Transaction Email Attachment Format in PDF
1. Navigate to Home > Set Preferences
2. Click Transactions tab
3. Transaction Email Attachment Format: Click PDF
4. Click Save

II. Send Email from Transaction Record
1. Navigate to Transactions > Sales > Create Invoices > Lists
2. Invoice: Click Edit
3. Click Communication
4. Click Messages
5. To Be Emailed: Enter Checkmark
6. Email Address: Enter Email
7. Click Save

III. View Email Sent
1. Click Communication
2. Click Messages
3. Email sent from Section II: Click View
4. Click Attachments

Note: Actual result is PDF Attachment Filename format: Invoice_xx_xxxxxxxxxx.pdf

The first numbers (Invoice_xx) shows the Invoice Transaction Number, while the rest (Invoice_xx_xxxxxxxxxx) is automatically generated by the system which is not editable.