With RouterOS an IP address is always active, even if an interface is down. Other venders handle this differently - and sometimes this behavior is expected. This script mimics this behavior.
Just install the script:
$ScriptInstallUpdate ip-addr-bridge;
... and make it run from scheduler:
/system/scheduler/add name=ip-addr-bridge on-event="/system/script/run ip-addr-bridge;" start-time=startup;
This will disable IP addresses on bridges without at least one running port. The IP address is enabled if at least one port is running.
Note that IP addresses on bridges without a single port (acting as loopback interface) are ignored.