SmartScreen on Defender is apparently causing delayed playback issues in videos on the latest Beta Channel build 22581 for Windows 11 Insiders. For now, there is a simple workaround for the bug.
Defender smartscreen RSS
Microsoft is providing more details on the "Block potentially unwanted apps' feature in its Chromium-based Edge browser. The feature is available in the stable branch starting with build 80.0.338.0.
