There's no differentiation between parameters background_color and background_image in sessionstart.hconf being empty or non-existent. In both cases, no colored background and/or no image is shown. The expected behavior would be non-existent --> hard-coded default value, same as out-of-the-box empty --> inactivated feature This would probably require either reworking tl-config/hivetool to reflect existing but empty parameters, or having tl-startup-bg read hiveconf directly.
