Only jobs that set a `totalAmount` of `Files` will get this, which is currently only the file copy jobs in KIO. I did the same in p-b-i and get beautiful download finished notifications now.
However, I don't really know the implications of just setting a total amount of Files, I surely don't want to see a "0 of 1 files" or "1 of 1 files" in every file download... Plasma doesn't do this, but I don't know about the widget file copy dialog.
Copied a jpeg file to somewhere else
Context menu has all the goodies
Copied a folder. When copying a bunch of files the parent folder is quite useful. However, when copying a folder it shows the parent of that folder instead of the folder that I copied, which isn't super ideal but a lot better than status quo.