The Z-Index Layers Viewer lists every z-index layer of the page with the layer number, the layer name, the highlight color and the number of objects on it. It opens with CTRL+J or the Layer Viewer button in the Edit Mode toolbar and takes the right edge of the window: opening it clears the selection and closes the properties panel, and selecting an object brings the properties panel back and closes the viewer.
Hovering a row highlights the objects of that layer on the page, clicking the row keeps the highlight until you click it again. Clear all highlights removes every kept highlight at once.
The crossed eye hides a whole layer while editing and the eye shows it again; Show all hidden layers restores every layer. Add layer creates a layer that no object uses yet, shown in italics with a delete button until an object uses it. Export JSON and Import JSON save and load the layer names and colors.
The list follows the page: adding, removing or re-layering objects while the viewer is open updates the rows and the counts.
Layer names, colors, and selection
The decorators of different objects also display the name and color of the layer they belong to, and every row of the Object Viewer carries a layer pill with the same information.
Clicking the Z-Index button, or the layer pill in the Object Viewer, opens the Z-Index layer selection window, where you can also add, import, or export layers.
Layer visibility can be changed during runtime with PageSetLayerVisibility and PageSetLayerVisibilityByName. See Page Scripts for more information.