that's because I inadvertently included that folder in my daily programmed backup (I don't do that usually because we don't need to back up those files that can always be regenerated in case... )
I optimise sequence by sequence after rougth cut, so daily backup is longer with those ProRes files . I have changed that external folder from now on. (older Optimised Files stay "linked" where they are.
no big deal anyway .
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