Microsoft just rolled out a Windows 11 preview build that could save you from those dreaded system crashes—and quietly patched a security hole that's been giving federal agencies headaches.

What's new: Preview build 26220.6982 in the Dev channel introduces Proactive Memory Diagnostics, a feature that'll tap you on the shoulder after your PC takes a tumble with a Black Screen of Death.

Here's the play: After a system crash, Windows 11 will suggest running a quick memory scan on your next restart. The whole thing takes under 5 minutes on average, and if it finds a memory gremlin causing trouble, Microsoft aims to fix it automatically—then let you know the coast is clear.

Why it matters: Picture this: instead of your PC repeatedly face-planting with mysterious crashes, Windows now acts like that neighbor who spots trouble before it gets worse. It's proactive troubleshooting in the spirit of Yankee ingenuity—catch the problem, fix it, move on.

The catch? You can always decline the scan if you're in a hurry and don't want to wait through the next reboot.

The other goodies: This build also brings a clever "copy and search" shortcut. Copy any text in Windows 11, and a highlight (what Microsoft calls a "paste gleam") pops up in the taskbar search box—click it, and your copied text jumps right in, ready to search. It's a small timesaver that adds up.

• Fancy hover animations for grouped taskbar apps are back after being paused
• Copilot+ PCs with AMD and Snapdragon chips can now use alternative cameras for Windows Studio Effects (previously Intel-only)

Between the lines: Microsoft disabled File Explorer's preview pane for downloaded files starting mid-October 2025—not just a random tweak, but a response to a nasty vulnerability chain involving NTLM credential leakage.

The technical backstory: CVE-2025-24054 and its follow-up bypasses (CVE-2025-50154, CVE-2025-59214) let specially crafted files leak authentication credentials when preview handlers tried to render them. Microsoft patched the original flaw back in March 2025, but attackers kept finding workarounds—hence the more aggressive fix.

Reality check: CISA added CVE-2025-24054 to its Known Exploited Vulnerabilities catalog on April 17, 2025, giving federal agencies until May 8, 2025 to mitigate. That's how serious this one was.

Be smart: You can still preview downloaded files if you trust them—just right-click, hit Properties, and click "Unblock." Or open them directly in their native app. For the security-conscious, consider blocking outbound SMB traffic (TCP 445) to untrusted networks and enforcing SMB signing.

What's next: These preview features typically graduate to stable releases within a few months, so expect Proactive Memory Diagnostics and the copy-search shortcut to hit mainstream Windows 11 (24H2 and 25H2) sometime in early 2026—assuming testing goes smoothly.