xnview wrote:you means that you want to start XnViewMP on double click on a file, and show fullscreen (like F11 in browser)?
Yes, a "fullscreen in priority" when double click on a file in windows explorer with option "Browser <> Full screen | Viewer mode <> Full screen " on meets his need.
for further suggestion, an option of entering "Browser mode", "Viewer mode" or "full screen" when double click on a image file in windows explorer would be best for universal demand.