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The view at the left shows all Apple system and security software updates in time order, with the oldest at the top, and the newest at the bottom. This order doesn’t change.
With each system software update, the list starts a new section; sections are shown with a disclose triangle ▸ at the left. To unfold any section, click on the disclose triangle or double-click on the text to the right of it. To fold a section back up, click on the triangle or double-click on the top line of that section.
For each line, SystHist gives the name of the update or installation, the official version number, and the date and time of installation in UTC. Adjust the widths of the columns by dragging the column headers as you wish. Those updates which are not for security purposes, such as Chinese Word List updates, are tabbed in to help you recognise them.
This view is most useful when you want to study the full history of installations on a Mac, as it shows them in a structured way. The data used for this are taken from /Library/Receipts/InstallHistory.plist
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