IE 10 and Firefox - Web Sockets Security Error

Vaadin 6 / 7 / 8
1

Hi,
why Vaadin 7.1.3 that support @Push not working with IE 10 and Firefox?
I have this error:

SCRIPT12152: WebSocket Error: Network Error 12152
Websocket closed, reason: Connection was closed abnormally (that is, with no close frame being sent). 
Websocket closed, wasClean: false
2

This just means that the App tried to use Websockets but it wasn’t supported by the browser so it switched to Streaming.
When you know you won’t use Websockets anyways you can default the transport to Streaming in the Push annotation (For more information look at the Enabling Push article on the Vaadin 7 wiki).