Set the Plays ("Play Count" before iTunes v9.2) of the selected tracks to a user-entered number (they will all be set to the same number). If this number is 0 then the Last Played date of each track will be erased. (iTunes has the ability to "Reset" Plays to 0 from a track's Info window.)
iCloud Music Library users should beware of a potential bug.
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Exports and then re-imports selected tracks' artwork
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Remove iTunes tracks disassociated from files
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Download selected media from a web page in Safari
downloaded 42m 27s ago
Batch merge and/or delete playlists
downloaded 1h 6m 38s ago
Batch-change the Album Rating for the albums of selected tracks