How do I undo/redo an annotation?
The undo and redo buttons allow you to undo or redo an action on your document.
Undo
From the toolbar, select the left-pointing arrow
to undo your last action. Press multiple times if needed to undo multiple actions.

Redo
From the toolbar, select the right-pointing arrow
to redo your last action. Press multiple times if needed to redo multiple actions.

Tip: You can also use a keyboard shortcut to undo an action
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Undo
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Mac: Command+Z Windows: Ctrl+Z |