tgp_ceremonial_candidacy_restriction_trigger

tgp_ceremonial_candidacy_restriction_trigger = {
	trigger_if = {
		limit = {
			exists = scope:target
			scope:actor ?= { tgp_realm_has_ceremonial_liege_trigger = yes }
			scope:secondary_recipient ?= { tgp_is_in_ceremonial_house_trigger = yes }
		}
		trigger_if = { # Top title only valid for ceremonial liege
			limit = {
				exists = scope:target.var:administrative_ui_special_title
				scope:target.holder = {
					OR = {
						has_realm_law = japanese_regency_succession_law
						has_realm_law = meritocratic_regency_succession_law
					}
				}
			}
			trigger_if = {
				limit = {
					top_liege.primary_title.var:administrative_ui_special_title.holder = { tgp_is_ceremonial_liege_trigger = yes }
				}
				custom_tooltip = {
					text = ceremonial_liege_only_heir_can_be_ruler_trigger
					scope:secondary_recipient = { tgp_is_ceremonial_liege_or_direct_heir_trigger = yes }
				}
			}
			trigger_else_if = {
				limit = {
					scope:actor = { is_independent_ruler = yes }
				}
				custom_tooltip = {
					text = ceremonial_liege_only_heir_can_be_ruler_trigger
					scope:secondary_recipient = scope:actor.player_heir
				}
			}
			trigger_else = {
				custom_tooltip = {
					text = ceremonial_liege_house_can_not_be_ruler_trigger
					scope:secondary_recipient = { tgp_is_ceremonial_liege_trigger = yes }
				}
			}
		}
		trigger_else = { # Governor titles only valid for non-ceremonial liege
			custom_tooltip = {
				text = ceremonial_liege_cannot_be_governor_trigger
				scope:secondary_recipient = { tgp_is_ceremonial_liege_trigger = no }
			}
		}
	}
}

As written in game/common/scripted_triggers/10_tgp_japan_triggers.txt.