Whilst viewing an image (double click file), I'd like to open / explore the containing folder.
Vainly searched for that option, though I am sure it is there.
(Preferences > Viewer > Mouse Buttons, regretfully there is no right mouse button)
There's a button on the default Viewer toolbar which opens the folder and selects the current file.
It might not be there if your toolbar dates back to an older version. You can factory-reset the toolbar to get it if you don't have changes you need to keep on it:
Alternatively, add a button to it which runs this:
Thanks. I have added a few things to the image viewer toolbar.
(Not sure about the toolbar date. No idea how to figure out.)
But .. by just adding the above button things work fine (of course).