See https://learn.microsoft.com/en-us/windows/release-health/windows11-release-information
(and Windows App SDK forum is off-topic...)
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Windows 11, Build 10.0.26100.2454 (released 01/2025), is this stable release
See https://learn.microsoft.com/en-us/windows/release-health/windows11-release-information
(and Windows App SDK forum is off-topic...)
If the question is about the Windows 11 SDK, then if it is listed here, then it is stable.