The outputs of the Render Layers node in the compositor in the startup file are missing. That's because add-ons are disabled when loading the startup file, so Cycles will not be registered by the time the node tree of the compositor is loaded, and its passes will not exist. To fix this, we mark the compositor node tree as needing an update after loading the startup file. Pull Request: https://projects.blender.org/blender/blender/pulls/125053