The toolkit is supposed to act as the UI manager for the asset editor. It's responsible for setting up viewports and most toolbars, except for the internals of the mode panel. However, because the toolkit also sets up the mode manager, and much of the important state is held in the mode managed by the mode manager, the toolkit also ends up initializing the mode. Thus, theFBaseCharacterFXEditorToolkitends up being the central place for the CharacterFX Asset Editor setup.