OS: MacOS 10.14 (Mojave)
To reproduce:
- Turn off option “Allow only one instance of XnView” and close XnView.
- In Finder, double click an image file ==> XnView will start and show the image.
- In Finder, double click another image file.
Expected behavior: A second XnView window will open, showing the second image. The first XnView window will continue showing the first image.