Complete King's Peace blocks all war even for the top liege if he is king-tier.

[zijistark]

Player is king-tier independent. With king_peace_2 on his crown law kingdom, no pressable weak claims alert:

Somebody who should qualify as a weak claim target:

Now switching off king_peace_2, the weak claims alert is back (and it's implied that she is included in the list):

I'm already 99% confident in the solution, so I'm self-assigning.