Apple Final Cut Pro X (10.0.9) - Manual (Page 260)

Chapter 11 Advanced editing 260
The way clips are grouped within the compound clip depends on where you selected the clips:
•
If you selected clips in an event: Final Cut Pro creates a new compound clip in the event
(in addition to the selected clips) and places duplicates of the selected clips in the
new compound clip horizontally, in the order in which you selected them. (For further
instructions on creating a compound clip in the Event Browser, see “Create an empty
compound clip,” below.)
Selected clips in the Event Browser
New compound clip
Compound
clip contents