...

src/calibre/devices/kobo/db.py

@@ -52,8 +52,8 @@ class Database:
         return self.conn.__enter__()
 
     def __exit__(self, exc_type, exc_value, tb) -> bool | None:
+        with closing(self.conn):
             suppress_exception = self.conn.__exit__(exc_type, exc_value, tb)
-        self.conn.close()
             if self.needs_copy and (suppress_exception or (exc_type is None and exc_value is None and tb is None)):
                 self.copy_db()
         return suppress_exception