GUI doesn't react to User Interaction after Download

Hi,
in this case i have a filterTable with beans which represent documents.
The table is in multiselect (Simple) mode and ther eis a “download”-button below the table which is enabled only if at least one item is selected (via valuechangelistener)
when this button is clicked a restservice is called which return a byte containing data for a zip-File.
I’m creating a StreamResource and the browser will ask the user to download the file which works fine.
Page.getCurrent().open(resource, “_self”, false)
After the user has downloaded or declined the download the gui doesn’t react to any user interaction.
e.g. click in the table (item is marked selected in the gui but no event is triggered), or interacting with other elements doesn’t trigger any more events.
I can only trigger events in the code after the download has happenend, but the user can’t.
Whats wrong?