2-3. Layer

Manages layers.
The layer of each frame is managed separately. Layer's number may be different between each frames.
The canvas size of a layer is fixed.
The order of layers can be changed by drag&drop. And a layer can be duplicated to other frames by dropping it into another frame.

Click to show or hide the layer. When you hold the Control-key down and click it, the same name layers of all frames are shown or hidden.

is switched with by clicking(when alpha channel or alpha blend is set). means that alpha channel (or alpha blend) is enabled, and means that it's disabled.

Click to show properties of the layer.

Menus

Add	Adds a new layer.
Duplicate	Adds a new layer duplicated from the current layer.
Delete	Deletes the current layer.
Combine	Adds a new layer duplicated from the current visible image.

Trash
Drag and drop a layer into the trash to delete the layer.

Drag&Drop into main window
Drag and drop a layer into main window to duplicate the layer as a new image. And original layer is deleted when dropping it, pushing Shift key.