You can use the Property inspector
to open a library item for editing, detach a selected library item
from its source file, or overwrite an item with the currently selected
library item.
Select a library item in a document.
Select one of these options in the Property inspector
(Window > Properties):
Src
Displays the filename and location of the source file for
the library item. You can’t edit this information.
Open
Opens the library item’s source file for editing. This is
equivalent to selecting the item in the Assets panel and clicking
the Edit button.
Detach From Original
Breaks the link between the selected library item and its source
file. You can edit the detached item in the document, but it’s no
longer a library item and isn’t updated when you change the original.
Recreate
Overwrites the original library item with the current selection.
Use this option to re-create library items if the original library
item is missing or has been accidentally deleted.