User devices are the largest contributor to media related global emissions. For web content, dark mode has been widely recommended as an energy-saving measure for certain display types. However, the energy savings achieved by dark mode may be undermined by user behaviour. This pilot study investigates the unintended consequences of dark mode adoption, revealing a rebound effect wherein users may increase display brightness when interacting with dark-themed web pages. This behaviour may negate the potential energy savings that dark mode offers. Our findings suggest that the energy efficiency benefits of dark mode are not as straightforward as commonly believed for display energy, and the interplay between content colourscheme and user behaviour must be carefully considered in sustainability guidelines and interventions.

翻译：用户设备是媒体类全球碳排放的最大贡献者。对于网页内容而言，暗色模式已被广泛推荐为针对某些显示类型的节能措施。然而，暗色模式所实现的节能效果可能因用户行为而受到削弱。本项初步研究探讨了采用暗色模式带来的非预期后果，揭示了一种反弹效应：用户在与深色主题网页交互时，可能会提高屏幕亮度。这种行为可能抵消暗色模式潜在带来的节能效益。我们的研究结果表明，暗色模式在显示能耗方面的能效优势并非如普遍认为的那样明确，内容配色方案与用户行为之间的相互作用必须在可持续性指南与干预措施中加以仔细考量。