Overview

• The capability was spotted by @phantomofearth in Windows 11 Dev/Beta build 26x20.6690, reviving Vista-era DreamScene functionality.
• Enabling requires the Windows Insider Program, turning on feature ID 57645315, and restarting the explorer.exe process.
• The preview supports popular formats including .mp4, .m4v, .mkv, .mov, .wmv, .avi, and .webm.
• Current implementation is desktop-only and does not extend to the lock screen, with videos playing on a loop in hands-on testing.
• Microsoft has not announced the feature or a rollout timeline, and effects on performance and battery life remain unclear.