Microsoft has released an update for Windows 11 Build 25163, which was released to Windows Insiders two days ago. It comes in the form of Cumulative Update Build 25163.1010 (KB5016904) and contains nothing new, as it is designed to test their servicing pipeline.
The full announcement says:
We are starting to roll out Cumulative Update Build 25163.1010 (KB5016904). This update does not include anything new and is designed to test our servicing pipeline for builds in the Dev Channel.
Hence, all the bug fixes and improvements that were announced with the earlier released build 25163 to the Dev Channel are carried over into this.
Interestingly, while there are no new changes made in this build, servicing test builds like these before have been known to break some features. For example, Windows 10 Build 21292.1010 caused issues for x64 emulation on ARM PCs.
The official announcement can be found on Microsoft's website here.