[raid 6.12.2 hangs after one day. No ping]

It's probably related to docker macvlan. I decided to shutdown pi-hole docker that is connected via br0. No problem for the moment, crossing fingers   

[raid 6.12.2 hangs after one day. No ping]

Same here. Since 6.12.1 (same with 6.12.2, but didn't tried 6.12.0), my unraid server stop being accessible after a "random" time (between 1h and 2d).