Cleanup orphaned messages

app/src/main/java/eu/faircode/email/DaoMessage.java

@@ -332,6 +332,11 @@ public interface DaoMessage {
             " AND NOT uid IS NULL")
     int deleteLocalMessages(long folder);
 
+    @Query("DELETE FROM message" +
+            " WHERE folder = :folder" +
+            " AND uid IS NULL")
+    int deleteOrphans(long folder);
+
     @Query("DELETE FROM message" +
             " WHERE folder = :folder" +
             " AND seen")

app/src/main/java/eu/faircode/email/ServiceSynchronize.java

@@ -2234,6 +2234,9 @@ public class ServiceSynchronize extends LifecycleService {
                     }
             }
 
+            // Delete not synchronized messages without uid
+            db.message().deleteOrphans(folder.id);
+
             db.folder().setFolderSyncState(folder.id, "downloading");
 
             //fp.add(IMAPFolder.FetchProfileItem.MESSAGE);