Handle the case where settings2 is missing, can't migrate from 3 -> 4

src/storage/migrations/mod.rs

@@ -289,7 +289,18 @@ impl Storage {
 
             Ok(())
         } else {
-            Err(ErrorKind::General("Settings missing.".to_string()).into())
+            if Self::MAX_MIGRATION_LEVEL <= 4 {
+                // At migraiton level < 4 we know this is safe to do:
+                let settings = crate::settings::Settings::default();
+                settings.save()?;
+                crate::globals::GLOBALS.status_queue.write().write(
+                    "Settings missing or corrupted. We had to reset to defaults. Sorry about that."
+                        .to_owned(),
+                );
+                Ok(())
+            } else {
+                Err(ErrorKind::General("Settings missing.".to_string()).into())
+            }
         }
     }
 }