Checking the system logs I noticed a lot of entries where WatchYourLAN container causes eth0 to enter and leave promiscuous mode with every scan, though I have promiscuous mode enabled for eth0 by default.

Here is a sample of what happens when I start the WatchYourLAN container from bottom to top
First I get a msg that eth0: renamed from vethxxxxxxx
Then an error about failing to add inotify watch
Followed by endless entries of eth0 entering and leaving promiscuous mode with every scan

[ 897.568886] device eth0 left promiscuous mode
[ 894.716647] device eth0 entered promiscuous mode
[ 834.382786] device eth0 left promiscuous mode
[ 831.534944] device eth0 entered promiscuous mode
[ 771.234860] device eth0 left promiscuous mode
[ 768.377606] device eth0 entered promiscuous mode
[ 708.058400] device eth0 left promiscuous mode
[ 705.203652] device eth0 entered promiscuous mode
[ 644.888788] device eth0 left promiscuous mode
[ 642.021651] device eth0 entered promiscuous mode
[ 581.619700] device eth0 left promiscuous mode
[ 578.722085] device eth0 entered promiscuous mode
[ 518.361540] device eth0 left promiscuous mode
[ 515.476176] device eth0 entered promiscuous mode
[ 455.013587] device eth0 left promiscuous mode
[ 452.153885] device eth0 entered promiscuous mode
[ 391.714720] device eth0 left promiscuous mode
[ 388.844361] device eth0 entered promiscuous mode
time="2023-08-05T11:08:05.835710358" level=warning msg="error from *cgroupsv2.Manager.EventChan" error="failed to add inotify watch for "/sys/fs/cgroup/system.slice/docker-62be058eefbda8eb3cef63911c4a0f9f4238b4cf35d5e2f038b17a39011c18e2.scope/memory.events": no such file or directory"
[ 388.160864] eth0: renamed from vethdd71689