In the devices category in the UMS Web App the filter only works for the directory selected in the directory tree. If multiple subdirectories exist in the selected parent directory it would be easier to have a search bar above the directory tree where you can search for devices (MAC address, IP address, serial number etc.) where afterwards the tree will expand the directory where the device is in.
We are in preparation for OS12 and most of our Development resources are focused on that main topic. Please be patient, we will continue our review of your suggestion in the meantime and try to put as much as we can in the OS12/upcoming ICG/UMS integration. Please stay tuned!
Will be part of UMS12. Archiving this FP.