In Origin earlier versions, the autosaved opju was deleted in the following two cases:
after successful save.
after project is closed.
Origin 2021b changed to make a copy of the autosaved opju before it is deleted on case 2(closing project). The file has a fixed name "Last-AutoSave.opju".
For any project in the AutoSave, Backup, Unsaved folders, Origin 2021b will
Skip saving Unsaved
No adding to Most Recent File List