Windows 11 build 25284

Windows 11 build 25284 is the ninth Insider Preview and the eighth available client build of Copper, the 23H2 development semester of Windows as a service. It was released to Windows Insiders in the Dev Channel on 25 January 2023, along with its server counterpart.

Windows Setup
The ability to format the drive as ReFS file system under the Setup instead of NTFS has been added. This change is disabled by default, but can be toggled on manually by enabling the  and   velocity IDs.

Miscellaneous

 * When search suggestions are triggered while using the Pinyin IME, keyboard focus will stay on the current candidate.
 * Unknown code changes have been made in the ReFS driver.

General

 * Fixed an issue which was causing certain apps to hang or crash when saving files as PDF.
 * Fixed an issue where using the cast option in an app may unexpectedly not show any devices.

Shell

 * Fixed an issue where right-clicking on certain icons in the hidden icons flyout would make the flyout dismiss rather than bringing up the context menu for that icon.
 * Fixed an  crash relating to the search box on the taskbar.
 * Fixed an issue where when using certain apps in full screen mode it wasn't possible to swipe down from the top of the screen to make the title bar appear.

General

 * This build is not publicly available to devices in the ARM64 architecture due to a bug that may cause a hang at the boot screen when resuming from sleep or hibernate.
 * Using Windows Hello to sign in with facial recognition may not work on certain ARM64 devices.
 * The system may take longer than expected to upgrade to this build in certain cases.
 * The screen may freeze when using the browser and certain apps, primarily media player apps.
 * Users may have issues when accessing websites and other resources via VPN connections.

Shell

 * The taskbar may sometimes be cropped in half when using the tablet-optimized taskbar.
 * On some locales, the default font used in several UI elements (such as the date and time on the taskbar) may change to regular Segoe UI instead of Segoe UI Variable.
 * The following issues will only apply if the new Spotlight UI is enabled:
 * Clicking on a secondary monitor may not dismiss the full screen experience.
 * Spotlight wallpaper may not show the correct resolution on multiple / mixed resolution monitors.
 * Users may not get a consistent refresh on a daily basis in certain cases.

Task Manager

 * Some dialogs may not render in the correct theme when applied from the Settings page.
 * The data content area of the Processes page may flash once when theme changes are applied in the Settings page.

Settings
Switching the Search entry point on the taskbar from the search box to the search icon via Personalization > Taskbar may fail in certain cases.

Widgets

 * Third-party widgets may occasionally disappear from the Widgets board. They can be re-added by clicking refresh or by re-pinning them from the widgets picker.
 * Third-party widgets may occasionally get unpinned when the Microsoft account is used to sign-in multiple Windows 11 devices.
 * The undo button on the widget pinned/unpinned toast notification may not work sometimes.

Safe mode

 * Quick Settings and date/time clock on the taskbar may be missing due to the  service not running.
 * Clicking Bluetooth & devices and Personalization pages may crash the Settings app due to an overrun of a stack-based buffer.