Welcome to the future, and the past.
This extension interacts with Time Machine on MacOS to give you the ability to see previous versions of files you are working on.
Activate the Time Capsule panel, by clicking its icon in the Activity Bar, or with the "Show Time Capsule" command in the Cmd-Shift-P palette.
When you open a file for editing, Time Capsule will check local APFS snapshots, along with any Time Machine backups on external storage. You do not need an external drive connected to use the local snapshots feature.
Click one of the dates in the sidebar to see a read-only copy of the file from that date. You can also display a diff by clicking on the diff icon you'll see when hovering over a date.
Snapshots are created (and removed) automatically by the OS, but you can manually make a snapshot if you want, with the camera icon in the snapshot panel. Making a snapshot doesn't guarantee it will stay around forever, it will get cleaned up by the OS automatically following the normal Time Machine rules.
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