Allow fallback values for appearance preferences

novelwriter/extensions/modified.py

@@ -44,6 +44,12 @@ class NComboBox(QComboBox):
             event.ignore()
         return
 
+    def setCurrentData(self, data: str, default: str) -> None:
+        """Set the current index from data, with a fallback."""
+        idx = self.findData(data)
+        self.setCurrentIndex(self.findData(default) if idx < 0 else idx)
+        return
+
 # END Class NComboBox