How do you specify a Helm chart value for a [] default?

I am trying to deploy Kibana from the Helm chart via an App in Rancher 2.2.8.
I want to mount in a CA certificate file for our internal CA authority, so I created a ConfigMap called elasticsearch-ca.

The Kibana chart description has the following to allow you to mount additional ConfigMaps:

Parameter 	        Description 	                        Default
extraConfigMapMounts 	Additional configmaps to be mounted 	[]

I don’t know what to put as the value for this in the Answers section. I have tried several formats:

['elasticsearch-ca']
[elasticsearch-ca]
"[elasticsearch-ca]"
["elasticsearch-ca"]
"elasticsearch-ca"

When I click on the app, it shows the following error (with whatever I put as the answer):

Wait helm template failed. Error: render error in "kibana/templates/deployment.yaml": template: kibana/templates/deployment.yaml:194:17: executing "kibana/templates/deployment.yaml" at <.Values.extraConfigM...>: range can't iterate over "elasticsearch-ca" : exit status 1

Hey!
For those guys and girls who came from google search:
You need to switch to YML editor and type something like that:

ingress: 
    hosts:
    - host: example.domain.ltd

It is equivalent for:

Parameter 	        Description 	                        Default
ingress.hosts           Ingress accepted hosts           []

Hi guys,
I think this is the answer what is being looked for:

In Terraform:

set {
name = “extraConfigMapMounts[0]”
value = “elasticsearch-ca”
}

With command line usage:

helm install mychart --set extraConfigMapMounts[0]=elasticsearch-ca

In terms of Helm it will create k8s resource in the YML format which was mentioned by @beshkenadze

Regards,
Taras.