connecting to udpbcast not possible on RPI

connecting to a udp Broadcast on a RPI seems not to be possible. I tried 2 raspis, none worked. on a windows machine, it works as expected.
running on windows: mavproxy --master=tcp:172.19.1.102:5762 --out=udpbcast:172.19.1.255:1111
running on RPI: mavproxy --master=udp:loopbackaddr:1111

can anyone confirm this?

Start by reproducing the two MAVProxy commands from the issue on a Raspberry Pi and Windows, then compare UDP broadcast behavior and any connection errors. Trace the `udpbcast` output path and the `udp:loopbackaddr` master path to identify where the platforms diverge. Done means Raspberry Pi can connect to the broadcast endpoint and the existing Windows behavior remains working.

Written by the indexing model from the issue text.