# KB5120998: Windows 11 25H2, 24H2 release preview build lands with long feature list

> **Open Intelligence Dossier** · First detected: 2026-08-15 08:07 UTC · Category: Technology

## Executive Summary
Microsoft rolls out update KB5120998 as a new Release Preview build for Windows 11 versions 25H2 and 24H2.

## Intelligence Brief
This build arrives alongside notable developments for multiple versions of the operating system, including versions 25H2, 24H2, and mentions of 26H1. Outlets report that the update delivers a substantial and long feature list for users testing the preview software. The rollout highlights active development cycles within Microsoft as the company prepares various improvements for its flagship operating system. Reporting from Windows Central emphasizes upcoming changes geared toward the Taskbar and Start menu components of Windows 11.


Meanwhile, coverage from Neowin details specific functional refinements within the latest Release Preview build, such as the inclusion of appropriate file size units for version 26H1. The presence of these distinct updates across multiple published articles indicates a broad deployment of preview features, capturing the attention of tech publications tracking Microsoft software pipelines. This trend builds upon ongoing testing phases for Windows 11 iterations, where preview builds serve as the primary testing ground before general availability. The introduction of major updates to core interface elements like the Start menu and Taskbar reflects continuous user interface iteration by Microsoft.


Coverage does not yet specify exact timelines for when these preview features will transition from the Release Preview channel to public retail releases for all users. Observers will monitor upcoming releases from Microsoft to track the progression of KB5120998 and related operating system builds through the testing channel. Future coverage is expected to document further refinements to file size units, Taskbar modifications, and Start menu enhancements as the software moves closer to deployment. Additional details regarding the full feature list included in KB5120998 will likely emerge as testers explore the preview build.

## Multi-Source Evidence Table
| Source Outlet | Headline | Verification URL |
|---|---|---|
| windowscentral.com | Microsoft gears up to ship major Taskbar and Start menu updates for Windows 11 | [Source Link](https://news.google.com/rss/articles/CBMi2gJBVV95cUxPQ1Z5V0ZGSGNnbXh2Q0NoUlhoS2JCVlJFai1EQXpDclJhaWtKQnFkNEJRM0IycFBIYjFxR1VBOTFPb3E5azFneHZjN3AyVDdVUjNWY3g4V0pueXF5RXpkMEdSWDUtREZIQTRSTUZqZ3lXQmMyWlhOQnlRV3UzNzJ3WHk2NW5NcW93ZDNjck5YSHpEX0wxMXVUajhKOHBxWE5Xa3VYcDdIOGkyRlNCdklkejNzTVZSUU4zUy1lYTgxOGF4cHNVZkpCd2F4NnFFMjlWaXpaa0Rob2hYQU9uOHNVSnFkYU9PdU1nRDZabWw0am1lcjN2Y3QzekdiUXp0Zzg1OHpVMjBNUVlOUHlYS3FGZlBsMlZCdVZZaVVNb1AxQ3AxMS1pTmpFWnRTNTl0d0FiSlFzeDZtMUFtVEd0Y1ZETHpObzZ3UjZ0ZWF2UDFzQlhRcVpDVlN) |
| Neowin | Windows 11 26H1 gets appropriate file size units in the latest Release Preview build | [Source Link](https://news.google.com/rss/articles/CBMiswFBVV95cUxPRW5QdlR4YkJiNS02aWhpOUJ6b2w2V2JuX3hJYTZWV3g2blRoWHQxbEh1WEozMmpTdC1CeDY3bEdzS3RCam9RNXRqRWw5Mk5ES3o0eGVvS0NuYmZlSTQ0T19SSzJmRzU1TUtoUWJUbUN1SV95c2VDSE9WUE16OHFvOVRFMHRpUEN5QXFIalhNX25PZ1doeVlyR1hCOFhnRFVpWkwxSVgzVE9KeVVLR1d4VUY0Yw?oc=5) |
| neowin.net | KB5120998: Windows 11 25H2, 24H2 release preview build lands with long feature list | [Source Link](https://news.google.com/rss/articles/CBMirwFBVV95cUxNUXJIaUh4UjBpTEZKUU9pY1pGMkdEenBCUXY4TDFaalp4TVdNUnhORGlnN3hGZk5fNno0blNsbjFsMURhWlJteTNQTE41N3g5cUk1b0EyLTdqTElseXNVVkJRVV9mVVVscFIxRkI0ZE1LZkFEaGJQbW1vTWY4QnB5M1JWUWEyanRmcnhycVBLNEFadDVtTzhRdE1sMTJxNEtKd1g3TDIzWkRFalgxU080?oc=5) |

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*Canonical Source: https://pulse.byoviral.com/trend/2026-08-15/kb5120998-windows-11-25h2-24h2-release-preview-build-lands-with-long-feature*