Standalone Sidebar Enabled

Standalone Sidebar is an optional mode for the Sidebar in Microsoft Edge. When this mode is activated by a user, the Sidebar appears in a fixed position on the Microsoft Windows desktop, and is hidden from the browser application frame.

If you enable or don't configure this policy, users can activate the Standalone Sidebar.
If you disable this policy, options to activate Standalone Sidebar can be hidden or made unavailable. Blocking 'HubsSidebarEnabled' (Show Hubs Sidebar) also prevents users from accessing Standalone Sidebar.