Choose Windows > Editors > Canvas Layer Editor to open the Canvas Layer Editor window.
Do one of the following:
That canvas automatically becomes the active canvas and its layers are displayed in the Canvas Layer Editor window.
If you don't see any layers in the Canvas Layer Editor, you may not have any canvas in your scene.
It is not possible to view all image layers for all canvas planes at once.
The layer thumbnails are turned off by default, to provide more space for the layer names. To see the thumbnails: