Holy crap super useful: I have just discovered that #TimeMachine on #macOS is really broken from High Sierra on. It consumes a crap ton of disk with "local snapshots". You can use 'tmutil thinlocalsnapshots' to free up that space. People online are reporting tens and hundreds of gigs of disk space freed up. (https://apple.stackexchange.com/questions/309143/how-to-thin-your-local-time-machine-snapshots-on-macos-high-sierra)
Another good blog: (https://derflounder.wordpress.com/2019/05/08/creating-managing-and-using-apple-file-system-snapshots-for-startup-drive-backups/)
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