In older versions of KDE in the default aplications section of Kcontrol there used to be a way to change the file manager see picture in link below. I don't see that anymore. I would like to change from Konqueror to Pcmanfm as my default. Is there a way to set that from the command line or a way to add back the file manager selection? I find that PCmanfm can be set to see many more types of thumbnails than Konqueror can and I find that very helpful.
https://cdn.ghacks.net/wp-content/uploads/2009/08/kde_default.png