How to see what connections are affected with mangling?

In firewall settings, only the Filter Rules have an Log option. If it is turned on, if connection matches rule, it is presented in log.

Source NAT, Dest NAT and Mangle rules do not have such option. How can I see what connections are affected by those rules?

You can mark connection in mangle, and then look up the specified connection mark in the “/ip firewall connection” table.

That is where I expected to find it but I see no such info in /ip firewall connection (MT 2.:sunglasses:

All I have are

FLAG
SRC-ADDRESS
DST-ADDRESS
PROTOCOL
TCP-STATE
TIMEOUT