AfterEffects
Layers and properties
Selecting and arranging layers
Select layers
Change the stacking order for selected layers
About coordinate systems
Move layers in space
Align or distribute layers in 2D space
Trim, extend, or slip-edit a layer
Remove part of a layer’s duration
Place a layer in time
Arrange layers in time sequentially
Copy or duplicate a layer
Split a layer
Auto-Orientation options
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