Microsoft shipped Windows 11 Insider Preview Build 26220.8925 to the Beta Channel on July 20, 2026, and with it came a trio of File Explorer tweaks that chip away at long-standing papercuts. The most immediately welcome change: Details view now automatically displays file sizes in the most readable unit—kilobytes, megabytes, or gigabytes—instead of forcing every value into a raw KB figure.
It is a preview build, not a retail update, and the features remain behind Microsoft’s controlled-rollout curtain. Beta Channel testers enrolled in the Windows 11 version 25H2 flight will see the bits first, and even they may not get every feature on day one. But the direction is encouraging, especially for anyone who has ever squinted at a seven-digit number and tried to divide by one million in their head.
Three changes, zero redesigns
Build 26220.8925 delivers its improvements through a small enablement package. No new visual style, no reorganized ribbon, no hidden Settings page. Just three specific, practical File Explorer refinements.
File sizes get a unit upgrade
In every previous shipping version of Windows 11, Details view would list every file size in kilobytes. A 4 GB ISO image would show as 4194304 KB. With this update, File Explorer now picks the most sensible unit automatically. A small text file still shows in KB, a music album in MB, and a virtual hard disk in GB. The change makes scanning a folder of mixed assets—documents, photos, disk images—immediately informative. No mental arithmetic required.
This behavior applies to the Size column in the default Details layout and in any view that includes the Size property. The column header now dynamically adapts, so a folder containing only two JPEGs might display a “KB” label, while a folder with a handful of movies switches the entire column to GB. The underlying data is unchanged; it is purely a presentation improvement, but one that makes everyday cleanup, backup, and transfer tasks noticeably smoother.
Middle-click spreads to more surfaces
Windows 11 has supported middle-clicking a folder to open it in a background tab for a while—but only in the main file pane and in the navigation pane. Build 26220.8925 extends that same gesture to two additional touchpoints: the address bar breadcrumbs and the Home page.
For the address bar, the usefulness is immediate. Imagine you are deep in a project folder, say C:\Users\Name\Documents\Projects\2026\Q3\Reports. Middle-click any breadcrumb segment—Projects, 2026, Q3—and it opens that location in a separate tab while your current folder stays right where it is. No right-click menu, no Ctrl+click workaround. The same middle-click works on the Home page, where Quick access pins and frequent folders live. Power users who juggle multiple directories for file comparison or drag-and-drop organization will find the gesture cuts out a step.
Conflict dialogs speak more clearly
The third change is invisible to most users but meaningful for those who rely on assistive technology. When you copy or move files into a folder that already contains items with the same name, Windows throws a conflict-resolution dialog: “Replace the file in the destination,” “Skip this file,” or “Compare information for both files.” The screen reader announcement for this dialog has been refined. Narrator and third-party screen readers should now present the options and consequences in a way that makes it easier to know which file is being compared and which action replaces what.
This is not a new feature; it is an accessibility bug-fix of sorts. The original announcements could be confusing, leaving users to guess whether they were about to overwrite the source or the destination file. The clearer feedback reduces that ambiguity.
What it means for you now—and later
The impact of Build 26220.8925 depends entirely on who you are and when you read this.
Home users and casual PC owners
If you are running the public release of Windows 11 (version 23H2 or earlier), these changes do not affect you yet. They are locked inside a Beta Channel build that will likely ship to all users as part of the eventual 25H2 feature update. When that update arrives—Microsoft has not announced a date—the file-size improvement alone will save you a few seconds every time you open a folder full of mixed media. The tab improvements will feel like a natural completion of the tabbed interface that first appeared in 2022. And if you use a screen reader, the conflict dialog clarity might prevent an accidental overwrite.
Power users and IT pros
For those already in the Beta Channel, or those considering joining, Build 26220.8925 is an easy quality-of-life upgrade. The middle-click extension is the standout here. File Explorer tabs have always been a productivity booster, but the inconsistent gesture support meant muscle memory often betrayed you when you reached for a breadcrumb. Now the behavior is uniform across the primary navigation surfaces. If you manage shared drives, compare log folders, or frequently hop between nested directories, you will feel the difference within an hour.
IT administrators managing Insider testing rings should note that the build is cumulative and delivered via a minor enablement package, making it lightweight to deploy. The features are not tied to any new policy or GPO that would require configuration—they simply appear when the rollout flag hits the machine. However, as with any preview, testing the build in a representative environment is wise before pushing it to wider rings.
Developers and accessibility advocates
The screen reader refinement, while small in code, signals continued attention to accessible file operations. Developers who test with assistive technologies can validate that the improved announcements work with their own custom dialogs or file-operation hooks. The underlying conflict-dialog framework has not changed, only the text provided to the accessibility API, so compatibility should be high.
How we got here: the gradual surgery of File Explorer
File Explorer’s modern arc began in Windows 11 version 22H2, when Microsoft introduced a tabbed interface—a feature that third-party tools had provided for years. Since then, the team has been layering quality-of-life improvements without fundamentally rewriting the shell. That approach makes sense: File Explorer is a crufty but deeply integrated component, and radical overhauls risk breaking countless workflows.
In 2023, Microsoft added the ability to drag tabs out into new windows and refined the right-click menu. In 2024, middle-click support for the navigation pane arrived. Build 26220.8925 continues that pattern, expanding middle-click to the address bar and Home page, and finally addressing the long-standing annoyance of KB-only size display.
The KB-only quirk wasn’t arbitrary. Internally, file sizes are stored in bytes, and the legacy API that retrieves them for display historically defaulted to a single unit. Changing that requires careful handling of sorting, column width calculations, and localization. That Microsoft chose to invest engineering time in this seemingly trivial improvement speaks to how much mundane file-management friction the team is willing to remove as part of the 25H2 release cycle.
The screen reader fix likewise reflects a broader push across Windows to make built-in experiences work well with assistive technologies without requiring users to employ special modes or settings. Following a series of Narrator improvements in earlier builds, the conflict-dialog announcement is a targeted fix for a scenario where a misunderstanding could lead to data loss.
What to do right now
If you are a Windows Insider in the Beta Channel running a 25H2 build, open Settings > Windows Update and check for updates. Build 26220.8925 should appear as a small cumulative update. Once installed, the file-size change and the new middle-click spots may appear immediately, or they may be staged behind Microsoft’s controlled feature rollout. To see if a feature is enabled on your device, you can watch for the behavior change: open a folder with large files in Details view, or try middle-clicking a breadcrumb in the address bar.
If the features are not visible, you can sometimes trigger their appearance by restarting File Explorer (via Task Manager) or rebooting, but there is no official client-side switch. Patience is the only guaranteed method.
For everyone else, the best action is no action. Wait for the public release. You can join the Insider program to get early builds, but the Beta Channel is not recommended for production machines. The file-size and tab improvements will eventually arrive with the 25H2 feature update, likely in the second half of 2026.
To verify your current build and version:
- Press Windows + I to open Settings.
- Go to System > About.
- Under “Windows specifications,” look for the Version (e.g., 23H2) and OS Build number.
What to watch next
Build 26220.8925 is minor, but it hints at Microsoft’s short-term File Explorer roadmap. Insiders may see further refinements to the address bar—perhaps drag-and-drop breadcrumbs or a history dropdown. The Home page is also ripe for improvement, with a possible interface for pinning cloud-based locations alongside local folders.
More broadly, the 25H2 update is expected to carry a handful of shell enhancements beyond File Explorer, including updates to the taskbar and notification system. Microsoft has not released a formal feature list, but the cadence suggests we will see a few more Beta builds in the coming weeks. For now, the auto-unit file size alone is enough to make any folder-cleanup session a little less tedious.