I am running Kubuntu 14.04 LTS on a Windows 8.1 host, and I am trying to get it to work with seamless mode. Using latest version of VirtualBox.
I have guest additions installed on the guest, and when entering a program and looking at the "view" menu, the "Seamless Mode" line is grayed out. The hotkey combination doesn't work either.
I double checked that the program is focused and things like that, also rebooted a couple of times. Also disabled nested paging.
Is there any way to test if the guest additions are working? Also, what should I do?