Comment 1 for bug 1828593

I can confirm that the position of a segment being downloaded is not saved when WM_DESTROY / WM_ENDSESSION received vs. it is saved upon WM_CLOSE.

In case of segmented downloads are disabled this means the whole download progress is getting lost. Probably that's happening with the reporter.
However, the looks like the temp file is there in the unifinished downloads folder, properly closed and after a restart the rechecker (Recheck integrity menu item) can restore the queue item to the previous download progress state just fine.

The saving of the queue when WM_ENDSESSION is received will not save the position of running segments because the changes indicator bit is set either at the finish of a segment or when the connection is closed before has been finished.

With default settings this problem will not cause any great loss; when it does (in case of segments disabled) then it can be still recovered manually for e.g. large files with slow speeds.