This is how my "Top Clients (blocked only)" list looks like:

Network list shows the device two times, which is correct. One MAC is the notebook itself, the other MAC is the docking station:

Versions:
Docker Tag [nightly]
Core vDev (development, edf33606)
FTL vDev (development, 7de40ae)
Web interface vDev (development, 0a962ba7)