Application session seems to continue after the browser tab is close.
If we need to support multi tab / window we implement the below:
https://vaadin.com/web/joonas/wiki/-/wiki/Main/Supporting+Multible+Tabs
however, the main window session is always remembered (until it is expired?)
Calling application.close is not feasible as the other windows that is still active still need the app
Putting ?restartApplication is not feasible as well as users will likely access it like normal website (e.g http://localhost/YourApplication)