In the activity screen Activity tab you can see a list of changes to the chosen elementdata item.
For example, in the screenshot below , you can see a list of changes to a data model:
If you click the + button (1 in screenshot) button it expands a panel that displaus displays information about a particular change.
You can see:
(2) the author of the change
(3) the difference between the old value before the change and the new value after the change
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