Alt + C does not copy, instead brings up Effect in menu

[uzernaam]

While in fullscreen view, I can Alt+M to move a file to a different folder, or Alt+C to copy it.

If viewing the file in tab mode (not fullscreen) I can Alt+M to move, but when trying to Alt+C to copy, the menu becomes highlighted and sometimes pulls down the Effect sub-menu.

How can I get Alt+C to work? I've double checked my keyboard shortcuts and they are what is expected and after several days of experimenting with other possible settings I cannot get it to work. This function works fine in XnView Classic, but I'm using MP now and prefer not to switch back.

[xnview]

yes known issue