Microsoft Defender for Office 365 is updating the quarantine email preview to simplify views, limit URL hover previews, and remove some "Load external content" buttons. Rollout starts November 2025, completing by mid-December. Users will see a clearer, more secure preview; no configuration changes are needed.
Applies to: Microsoft Defender XDR
Source: mc.merill.net — data via Merill Fernando's open archive (MIT).