ive been experiencing this issue for the last 3 or 4 weeks....
only started after use of an existing "working" file that work was lost on when c2 crashed on exporting ... i removed the extension from the backup file...got my work back, then the weirdness started to happen.
personally i have seen this happen ONLY on files that i have had to recover (removing the backup Extension)
but a co-worker started seeing the issue when she was trying to cloud sync to google drive.
i constantly work from files on dropBox as well as google drive and havent seen this happen yet....
im sure this doesnt help at all .... but figured i would chime in with my experiences and findings
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