Overview

• Insiders have found a hidden setting in recent Dev and Beta builds (including Build 26220+) that lets users set videos as desktop backgrounds.
• Testers can enable feature ID 57645315 and restart explorer.exe to surface the option in Settings, according to step-by-step reports.
• Supported formats in the preview include .mp4, .m4v, .mkv, .mov, .wmv, .avi, and .webm, and playback loops on the desktop but not on the lock screen.
• Hands-on reports describe non-interactive, desktop-only playback that may leverage DWM and Media Foundation, with one tester noting no meaningful power impact in brief use.
• Microsoft has not announced the feature, which evokes Vista’s DreamScene, and early notes indicate limits on very large or long videos compared with richer third‑party tools like Wallpaper Engine.