Portal 7.3: When user logoff close all pop-up windows

Hello.

We are implementing portal 7.3 and have a business requirement to close all portal pop-up windows when a user log off from portal.

Users can open portal applications which will open in pop-up windows. When they log off from portal, those applications in pop-up windows should also be closed. Is there anyway we can force the pop-up window to close along with portal log off action?

I know each browser window is independent and may not be controlled from triggering event in another window to force close. Let me know if there is any way we can achieve this.

Appreciate your response.

Thanks