Motion Collapse and expand group hierarchies
To make the Layers list easier to manage, you can collapse layers nested in a group. Collapsed groups appear as a single row in the Layers list, and can be moved or nested like any other layer. Each group’s thumbnail displays a preview of its composite, making it easy to see what’s nested inside when the group is collapsed.
Open or collapse a single group
Do one of the following:
In the Layers list, click the disclosure triangle to the left of a group’s name and icon.
Press the Up Arrow and Down Arrow keys to navigate up and down the Layers list, then press Option–Right Arrow to open a group or Option–Left Arrow to collapse a group.