You can select a region to add blank playback time into your project (which will appear
black in the Canvas). For example, you might want to add some black frames between
two objects, or add frames in as a placeholder for a clip you don’t yet have. This is called
To insert time into a project
Holding down the Command and Option keys, drag in the ruler.
Drag as wide an area as you want to insert.
Choose Edit > Insert Time.
The number of frames in the region is added to the project, beginning at the end of the
selected region and pushing any existing objects further out in time.
If time is inserted during a range that contains a video clip, the clip is split onto two tracks
and objects beyond the split point are placed in a new group.