Adobe After Effects - Manual (Page 26)

Dragging panel (A) onto docking zone (B) to dock it (C)
Grouping zones
Grouping zones exist in the middle of a panel or group, and along the tab area of panels. Dropping a panel on a grouping zone stacks it with other
panels.
Dragging panel (A) onto grouping zone (B) to group it with existing panels (C)
Dock or group panels
1. If the panel you want to dock or group is not visible, choose it from the Window menu.
2. Do one of the following:
To move an individual panel, drag the gripper area in the upper-left corner of a panel’s tab onto the desired drop zone.
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