The kernel package now includes the vboxguest driver for Virtual Box Guest
virtualbox-guest-additions package, which provides
support for better integration of VirtualBox guests with the host, is also
included. Features include:
Automatic resizing of the guest desktop-resolution to the vm’s window-size
Seamless mode support (only show guest windows, hide guest background)
Copy and paste between guest and host
All of these features are enabled by default in Fedora Workstation.