[Users] Unable to Resize VM Disk in oVirt 3.3 (Upgraded from 3.2)

Hello, I upgraded our installation of oVirt from 3.2 to 3.3, and one of the features I was looking forward to was the ability to resize VM disk. However, it appears that the feature is still not available to me. I selected the "Virtual Machines" tab, selected a VM, selected the "Disks" sub-tab, and selected a disk; but the "Edit" button is grayed out. The disk status is "OK" and the VM status is "Up". Help is appreciated.