@Phineas ,
If you set the OnSuccess of the Form to
Set(
gblID,
Self.LastSubmit.ID
)
You can preview it after it is submitted by this
"https://yourdomainname.sharepoint.com/_layouts/15/getpreview.ashx?path=" & First(
LookUp(
YourSPListName,
ID = gblID
).Attachments
).AbsoluteUri
but there is no way of previewing a PDF directly from an attachment control (you can only do this with image files)
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