Monday’s Windows 11 update (KB5070311) contains an unnerving bug. When users open File Explorer in dark mode, it briefly shows a full-screen white flash before the icons and folders appear. This can be jarring, especially on large or bright screens.
Microsoft has counted the bug among KB5070311’s known issues, noting that it can manifest in other scenarios, too. The white flash has appeared when users jump between the Home and Gallery views, create a new tab, toggle the Details pane, or choose “More details” in file copy dialogs. Worse, the white flash doesn’t fire every time, making it harder to anticipate.
KB5070311 was supposed to make dark mode more consistent across the Windows 11 UI, including in system dialogs. The bug appears to come from those changes to File Explorer’s interface. Microsoft says it is investigating the issue and plans to release a fix in a future Windows update, though it hasn’t yet specified a date.
Users who find the flash disruptive can switch File Explorer to light mode, avoid installing this optional preview update, or roll it back through the Windows Update history page.