Created attachment 138872 [details]
screenshot of device selection in systemmonitor

SETTING
I have a bridge device "br0" configured as my main network interface. My real interface eno1 is added to that bridge. Only the bridge gets a ip-adress assigned via DHCP, not eno1. This is a static openrc configuration without Networkmanager. 

OBSERVED RESULT
I am unable to select the bridge device br0 as network device in systemmonitor

EXPECTED RESULT
I can select br0 as network device in systemmonitor

This is important, as eno1 does not proved useful information as a device. E.g. the ip-address is unset and so I am unable to display it in systemmonitor. 

SYSTEM INFO

Openrc device configuratoin
$ cat /etc/conf.d/net
config_eno1="null"
bridge_br0="eno1"
bridge_forward_delay_br0=0
bridge_hello_time_br0=1000
bridge_stp_state_br0=0
config_br0="dhcp"
dhcp_br0="nontp nonis"

$ ifconfig 
br0: flags=4419<UP,BROADCAST,RUNNING,PROMISC,MULTICAST>  mtu 1500
        inet 192.168.2.72  netmask 255.255.255.128  broadcast 192.168.2.127
        inet6 fe80::1597:94b3:db39:b013  prefixlen 64  scopeid 0x20<link>
        ether 62:84:0b:29:b5:cd  txqueuelen 1000  (Ethernet)
        RX packets 3778751  bytes 5270969401 (4.9 GiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 1790815  bytes 186071425 (177.4 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

eno1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet6 fe80::76d4:35ff:fee8:458  prefixlen 64  scopeid 0x20<link>
        ether 74:d4:35:e8:04:58  txqueuelen 1000  (Ethernet)
        RX packets 3893612  bytes 5347066971 (4.9 GiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 1793814  bytes 193861071 (184.8 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device interrupt 20  memory 0xf7400000-f7420000 

Operating System: Gentoo Linux
KDE Plasma Version: 5.21.5
KDE Frameworks Version: 5.82.0
Qt Version: 5.15.2
Kernel Version: 5.12.6-gentoo
OS Type: 64-bit
Graphics Platform: X11
Processors: 8 × Intel® Core™ i7-4790K CPU @ 4.00GHz
Memory: 23.4 GiB of RAM
Graphics Processor: NVIDIA GeForce GTX 970/PCIe/SSE2