Scheduled Maintenance: We are aware of an issue with Google, AOL, and Yahoo services as email providers which are blocking new registrations. We are trying to fix the issue and we have several internal and external support tickets in process to resolve the issue. Please see: viewtopic.php?t=158230
Still, if you run it on the host it affects the guest's display too, so not a major issue. If anyone has any insight as to why (or knows a good way to do it), it'd be good to know though.
You can try it fairly safely on bare metal of course, since if you do it twice you should end up exactly back where you started. I'm saying nothing about taste. Some websites look... a little funky
Another slight pain point for me is I've got a laptop that's more or less constantly plugged into an external monitor. I can't figure out how to get this to affect that too - as far as I know it's still considered part of 'display :0', but it ignores it.