Virtualbox guests no longer getting shortcuts?

I've been using Virtualbox with Ubuntu for a few years now, and I've noticed a change in behavior of keyboard shortcuts sometime recently, possibly after a new version update: in the past, when the guest had the keyboard focus, I was unable to use most of the host's keyboard shortcuts, such as switching virtual desktops; I had to either click on the host desktop, if I could, or, I later found, I could use AWN (in the auto-hide mode) to make use of its desktop switcher applet.

However... now I can no longer get the guest keyboard shortcuts to work at all. None of them will work any longer, even with the same VMs I've always used.

I haven't found any settings for this, which would be ideal, as I can see some situations where this would be a feature, but overall, I'd like them to work like they did previously, where I was able to do things like switch virtual desktops or run a terminal with a hotkey.

I just discovered something I've been missing - the "Preferences" menu item. I've gone through the settings for the individual VMs many times, but didn't notice that there was a separate "Preferences" menu for some reason. I opened this, and lo and behold, there was a checkbox under "Input" (where the host key is set, another thing I was wondering about) called "Auto Capture Keyboard". This was unchecked, for some reason, and checking this made it behave like it did previously.

It would be nice if this were set per VM, but the good news is that it can be changed while the VM is running, and takes effect immediately. So, problem solved. User is an idiot. :(