Hi,
I would like to allow user open mutliple instance of my vaadin application but I don’t know how I can realize this.
Maybe I have to declare mutliple JSESSIONID? Or I can do this with vaadin window (https://vaadin.com/book/-/page/application.windows.html).
Thanks for your idea 
Aurelien
Hi,
There is only one application instance per session but to support multible browser windows, you can override the Application.createWindow(String name) method. For more info, take a look at
here
.
If a user just does “New Window”, you’re in the same session. If you can educate the users to use a desktop shortcut (as on Windows) then you can add “-nomerge” to an Internet Explorer shortcut and the shortcut will create a new browser process with different sessions. Other browsers such as Firefox and Chrome have no such option, to my knowledge, other than deep in their development debugging plugins.
It is therefore safest to plan for the fact that a single user may have different Vaadin windows, all in the same session, with several windows showing the same view (but different occurrences of the view). This requires being very strict about local variables.