This was very easy with FCP7 but not sure how to do it in FCPX. I have a project, I want to consolidate only the media used in the project + not all my media or a specific event as the timeline uses footage from many events, and media manage onto an external drive.
Highlight the project(s). Choose file>copy project to new library. Once you've created the new library (it'll only include the used media) open the library pane in the inspector and choose to consolidate the media. That will ensure all the media is copied to the library or desired external location (in this case I'd choose library to keep it all contained and portable). Failure to do so will leave any external links as aliases to the media and not copy it.
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