The Windows Sidebar, introduced as a gadget presentation and development platform in Windows Vista, ships in Windows 7 as the Windows Gadget Platform, and is the new framework for creating and ...

This tutorial explains how to hide or show Phone Link Sidebar on Start menu in Windows 11 using the Settings app and Windows Registry.

This is only when right-clicking a sidebar item, not the main contents of the window. Kind of annoying since this is typically how I open new windows when copying between directories.