But you will have some history available, to roll back through multiple versions. Dated backups will then accumulate and will need periodic pruning. One idea may be to locate your Catalog elsewhere, outside the OneDrive synced area, but then to set a folder within this area as the destination for your LrC catalog backups (made cleanly, as you determine, on exiting LrC hence known to be suitable for restoring). Previews could always be generated again if that was ever needed. It's really the Catalog itself which matters, besides the source image files. It is at best impossible, and at worst inadvisable, to back up the Catalog itself while in use - the database and its indexes may not be in a clean and consistent state at that instant. All kinds of previews live in subfolders of the Catalog location, constantly changing, and it is IMO a pure needless waste of effort to keep backing those up continually. IMO this is an inappropriate place for certainly the Catalog to live, even more so once that is syncing to OneDrive. LrC's install default is to create a Catalog within Pictures, and then to offer to import all image files within Pictures and subfolders thereof. I did this recently, incautiously, and the file system locations of my Documents, Pictures and Desktop were changed to sit within a 'OneDrive' folder representing the local instance of the OneDrive synced data. And that will include your Pictures folder. IMO the most likely, is that you have accepted for OneDrive to keep your personal drives backed up to cloud. If any of these locations are withiin a part of your file system that is being synced to OneDrive, then any change will then incur some OneDrive activity - which may or may not be useful or appropriate. You also have, separately, control over where output files are to be saved. You have control over two aspects of LrC working: where your Catalog and its support files live (previews, chiefly) - and, where your imported image files live (camera Raws / JPGs, derived files such as PS edited versions saved in PSD / TIF) live.

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