hello for all ..!
in Mikrotik router - default firewall setting - chain:input. Dst Add:127.0.0.1
action :accept
please anyone know what is the benefit of this rule..?
It’s in the comment of that rule.
And to make it explicit:
add action=accept chain=input comment="defconf: accept to local loopback (for CAPsMAN)" dst-address=127.0.0.1
More information on CAPsMAN:
https://help.mikrotik.com/docs/pages/viewpage.action?pageId=1409149
And not commented: is wanted also for Wireguard.
Generally is local loopback interface, and is better if is working and not blocked.
WHY is that needed for wireguard?? and why is it needed if not using capsman.
Your answer lacks the educational components to learn from such wisdom. 
Is there a hidden teacher locked in that icy stare??