Visual Studio – Open Recent in a new Window

   "window.openFilesInNewWindow": "on",

Controls if files should open in a new window.

• default: files will open in the window with the files’ folder open or the last active window unless opened via the dock or from
  finder (macOS only)
• on: files will open in a new window
• off: files will open in the window with the files’ folder open or the last active window

Note that there can still be cases where this setting is ignored (e.g. when using the -new-window or -reuse-window command line
option).

  "window.openFoldersInNewWindow": "on",

Controls if folders should open in a new window or replace the last
active window.

• default: folders will open in a new window unless a folder is picked from within the application (e.g. via the File menu)
• on: folders will open in a new window
• off: folders will replace the last active window

Note that there can still be cases where this setting is ignored (e.g.
when using the -new-window or -reuse-window command line option).

Those should do the trick. In your settings.json.