Originally Posted by
DarioCrivelli
The reported request for control.js, with LS_op=destroy, can be made by the Client Library anytime a session gets closed.
The purpose is to make sure that the session is also closed on the server side, because there may be intermediate nodes in the path to the Server that keep their socket open.
So, the request is most of the time redundant and it may end up in a "sync error", which is not an error indeed.
If I understand well, in the described situation it is expect that some session closes.
On the other hand, the LS_session=blah parameter would be strange; I assume "blah" is your own placeholder.