About the Palette sidebar
This sidebar provides a place to open and view sets of modules or custom palettes that you build for yourself.
When you open the Palette sidebar, it appears on the left side of the Workbench in the sidebar pane.

From the Palette sidebar, you can open multiple palettes, close palettes and view modules within palettes. You may also double-click or use popup menus to perform all operations that are available from the Palette sidebar (for example, copy modules, select a module view, refresh the tree node, and more). The expandable tree provided in the palette allows you to perform actions on nodes within the palette and to navigate through the palette sub-directories. Items are displayed in the tree with an icon that represents an associated function or file type.

Palette previews display in the palette when components have images configured either as the default image property or as the image assigned to the comPreviewWidget property. If no preview is associated with a component, you can add a compPreviewWidget property to a widget to display an image in the preview pane of the palette sidebar.