New pop-up on 4.3.4

[J-Phil]

I've been happily running and recommending VirtualBox for a few years. Primarily for Windows 7 guest in OSX (now Mavericks).

After upgrading to 4.3.4, when I launch my virtual machine, I now get a popup box with a progress bar that is always at 0% saying

Creating process for virtual machine "<my machine name here> (GUI/Qt) ... (1/2)"

It doesn't seem to stop my virtual machine from working; it just sits there on the screen, with no close button. It has a (X) cancel button which when presses, does nothing at all.

Any idea about this please? I'm happy to just ignore but if there is a preference that says 'Show VirtualBox Manager statuses' then I'd choose to turn it off

[Edited] - now have found when clicking cancel, it seems to hang the VirtualBox Manager but the guest machine continues happily.

[noteirak]

Do you have a 100% reproducible scenario for this?