A Microsoft file hosting and synchronization service.
This happens with a number of files. If I copy one of the bloated files and make a minor change, the file size on OneDrive is correct. It appears that the bloated files are ones I have worked on recently. I’m wondering if the increased size is due to retaining prior versions before I turned that option off. That is, although I asked OneDrive not to save prior versions, files that had done so did not jettison the prior versions anyway.