If you’re on the beta, under Taskbar settings > Taskbar behaviors, you can now select options under Show smaller taskbar buttons: Always, Never, or When taskbar is full. The third option will scale down icons so that they all can fit and not get hidden away in a second menu.
The behavior appears to be similar to macOS where icons on the dock get smaller as more applications or minimized windows are added.
X user phantomofearth, who frequently digs through Insider builds, posted that there’s an update to the Start menu as well. Now, it has a larger layout that includes the ability to hide the recommended recent apps and can show all of your apps on the page.
[Notigroup Newsroom in collaboration with other media outlets, with information from the following sources]
