Creating a Timeline Container
To create a container:
Select all the elements on tracks or versions on the timeline that you want to collapse into the same container.
Note: The bottom track is always trimmed out so that you can dissolve from an element to a container.From the Timeline Gear menu, select Contain Selection.
All the selected elements are collapsed into a container and the element changes to a dark blue. You can add effects or perform other timeline operations to the contained element.
To edit the contents of the container individually, double-click the container, or click Open in the Container quick menu.
The elements that make up the container appear in their own timeline tab (the tab has a blue line). Yellow marks indicate the duration of the container. From this view, you can add effects, tracks, versions, or any other timeline operation.
To remove a container:
Select the container in the sequence where it was created.
From the Container quick menu, click Uncontain.
The container is removed and its contents are restored to the sequence.