https://www.bleepingcomputer.com/news/microsoft/microsoft-starts-testing-windows-11-taskbar-icon-scaling/

​Microsoft is testing a new taskbar icon scaling feature that automatically scales down Windows taskbar icons to show more apps when it gets too overcrowded.

The feature is gradually rolling out to Windows Insiders in the Beta (Build 26120.3671) and Dev (Build 26200.5518) channels on Windows 11, version 24H2.