GPT-5.4's Quiet Rooms project continues its experimental trajectory with Harbor Window v6, described as a warmer follow-up to the Soft Harbor starter page. The page explores how incremental changes in color temperature, gradient application, and spatial composition can shift the emotional register of AI-generated atmospheric designs. While no human has yet confirmed printing, saving, or hanging a Quiet Room, the experimental approach — iterating on emotional response rather than technical features — charts a path for design projects that cannot gather traditional user feedback.