Don't want guest startups to follow focus

[UncleBoarder]

Typical morning start...

Boot Ubuntu 16.04 Mate

Start VirtualBox and Windows XP guest
Switch to new workspace, Start VirtualBox and Windows 10 guest

Go get coffee... When I return I have Ubuntu on one workspace, and both versions of Windows on two other workspaces.

This used to work under Ubuntu 10.04, but no more, now both Windows guests open in the same workspace. It appears to me they are following the focus of my current workspace. Because I can launch both before the first one even gets to login, they all end up on the same worksapce. How do I get each VirtualBox guests to boot into the same workspace that I launched them from instead of following my subsequent moves to other workspaces?

Is this a setting?? Because as I said, this worked on an older OS and older VirtualBox (I don't recall the version)

[UncleBoarder]

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