Microsoft has released an update to Windows 11 version 26H1, OS Build 28000.2113, through cumulative update KB5089548 on May 12, 2026. This update includes essential security fixes and non-security enhancements from the previous month's optional preview. Windows 11 version 26H1 is specifically designed for new devices launching in early 2026 and will not be available as an in-place update for existing systems running versions 24H2 or 25H2. The update focuses on maintenance for this branch, with improvements in SSDP notifications and gaming compatibility. It also includes AI enhancements exclusive to Copilot+-enabled PCs. Microsoft continues to support versions 24H2 and 25H2 for enterprise deployments, while 26H1 is relevant only for new hardware platforms. Currently, there are no known issues reported for Windows 11 26H1 or update KB5089548.