Verified in ovirt-engine-3.4.0-0.7.beta2.el6.noarch.
Verification steps:
1. Have a running VM with SPICE/VNC console, "Native Client" invocation set in Console Options.
2. Click the Console button.
Results:
The console.vv file download is invoked in the same window/tab, no other pop-ups/windows are opened.
Clients used:
Firefox 24 ESR @ RHEL 6.5
IE 9 @ Windows 7