Microsoft has added a new flag to Edge Canary aimed at adapting the design of the browser UI either to Windows 10 or Windows 11, depending on what you are running.
The “Enable Windows 11 Visual Updates” flag claims to enable “in-progress visuals appropriate for your currently installed version of Windows.”
When enabled, the flag appears to deliver the same change on both Windows 10 and Windows 11, mainly a change to the font style and size.
An example of the change, which is present in most browser menus, can be seen above. There does not appear to be any other changes, though of course, this may change over time.
Source: Leo Varela