The issue is a chicken and egg problem. Without scribus installed, nautilus has no knowledge at all of what a scribus file is, so it correctly identifies the file as a standard xml file (as that is basically all it is really), and picks an existing application that handles xml files (and Firefox is more than capable of viewing xml files)
The issue is a chicken and egg problem. Without scribus installed, nautilus has no knowledge at all of what a scribus file is, so it correctly identifies the file as a standard xml file (as that is basically all it is really), and picks an existing application that handles xml files (and Firefox is more than capable of viewing xml files)