I have a sidebar application, I am using an IM functionality inside this sidebar. When a user is logging in, the connection with chat server will generate on this sidebar.The sidebar itself acts as a parent window. When a user click on the IM icon inside the sidebar, a child Pop up window will open. The child Pop up window uses the connection objects from the Parent sidebar. When closing this child Pop up window, the sidebar hangs. When I tried to repoen the child Popup window, the Pop up window also hangs for a long time. But I can not find the exact reason behind this hanging of sidebar, after closing the Pop up window.