Reproduction #1
1.) Open a picture in view mode in XnViewMP 0.56 (I open from "recent files")
2.) Right-click on the picture in view mode and use "Open in file explorer"
3.) Nothing happens
Reproduction #2
1.) Use clean XnViewMP 0.56
2.) Go to Settings and enable "Multiple view for same file"
2.) Open a picture in view mode in XnViewMP 0.56
3.) Right-click on the picture in view mode and use "Open in file explorer"...
4.) Picture will then open in duplicate tab!

Please investigate and fix these, very important