When you load a custom library, the Content Manager panel opens automatically. The Content Manager is used to create, view, and edit assets such as Components, Symbols, Footprints, and 3D Packages.

Figure 1: Default location of the Content Manager panel in an electronics library.
You can also use the Content Manager in order to preform various actions on 3D Packages such as Update to latest version and importing library.io packages into your current hub.