Microsoftは1月16日(現地時間)、Windows 11のWindows Insider ProgramのBetaチャンネル向けの最新ビルド「Windows 11 Insider Preview Build 26220.7653(KB5074157)」をリリースしました(Windows Blog)。Windows 11 Version 25H2でBetaチャンネルを使用しているWindows Insidersは、有効化パッケージ(Build 26220.xxxx)を介してWindows 11 Version 25H2に基づくアップデートを受け取ります。新機能をいち早く使用したい場合、Windows Updateの設定画面で「利用可能になったらすぐに最新の更新プログラムを入手する」をオンに変更します。Build 26220.7653の新機能Build 26220.7653には、アカウント設定UIの刷新、Click to Doの改良、壁紙の.webp形式の画像への対応などの変更が含まれています。リリースノートは以下の通りです。Changes and Improvements gradually being rolled out with toggle on*[Account Settings]We’re updating the design of dialogs in “Accounts > Other Users” based on modern WinUI framework with support for dark mode:Please note that the visibility of the above dialog option depends on whether a domain joined work or school account is configured on the device.Feedback: Please share your feedback in Feedback Hub (WIN + F) under “Settings -> User Profile Account Settings.[Click to Do]The Copilot prompt suggestions in Click to Do will now load instantly. This change is not yet rolling out to Windows Insiders in the EEA (European Economic Area) or China.[Desktop Background]You can now set .webp images for your desktop background in Settings > Personalization > Desktop Background.Fixes gradually being rolled out with toggle on*[Taskbar and System Tray]Fixed an issue in the latest builds where, when the taskbar was set to autohide, it might invoke before interacting with the bottom of the screen, blocking the use of apps in that area.Fixed a recent issue which was causing the Start menu, notification center, and quick settings to not open on click sometimes, although using the keyboard shortcuts for each of these still worked.[Start menu]Fixed a memory leak when opening the Start menu, which could lead to performance issues over time.Fixed an issue for Arabic and Hebrew users, where Start menu was opening on the wrong side of the screen when the taskbar icons weren’t centered.Fixed an issue where if you opened a folder of pinned apps in Start menu and tried to pan it with touch, it would dismiss Start menu.[Bluetooth]Fixed an issue causing Bluetooth device battery level to not show for some Insiders after the latest builds, even though the devices supported it.[Xbox full screen experience for PC]This build fixes some unexpected app and game behavior when using FSE. We’re continuing to validate scenarios and as such keeping the known issue active for now. Thank you Insiders that have been sharing feedback![Login and Lock Screens]Fixed an issue which could cause the password icon to appear blank on the login screen.[Settings]Fixed an issue causing Settings to crash when interacting with audio devices in the last two builds.Fixed an issue where the keyboard character repeat delay in Settings > Bluetooth & Devices > Keyboard was backwards from how it was set in the backend.[Other]Fixed a few issues with clipped text in msinfo32 when using a high display scaling.Fixed an issue impacting some Insiders where clicking on .appinstaller files to install MSIX packages was unexpectedly failing with an invalid argument error.Fixed an underlying issue which was causing Notepad to not display an underscore in text with certain fonts when your display was set to 125%.Fixed an underlying issue which could cause explorer.exe to hang when first logging into your PC, if certain apps were configured as startup apps. This could make the taskbar not appear.Known issues[Xbox full screen experience for PC]Some apps may behave unexpectedly when using FSE, particularly those that expect to be locked to a given size or launch additional windows.[Taskbar & System Tray]We’re investigating an issue where for some Insiders apps aren’t showing in the system tray when they should be.[Display & Graphics][NEW] We’re working on the fix for an issue causing secondary monitors to not display correctly and show black screens after the latest updates for a small number of Insiders.[Click to Do]We’re working on the fix for an issue where the Microsoft 365 Copilot prompt box on selected images does not function if the Microsoft 365 Copilot app is not running.公式ブログには細かな変更内容がリストアップされていますので、インストールする前に確認することをおすすめします。