Count number of keys in json return

[jerry_onscreeninc.com]

I have a Firestore database and in it, I have a field with an array of json objects

When I get the data back for the collection, I want to add a simple column that counts how many items are in "participants". I have selected json as the column type for participants, but I get errors trying to get participants.length.

It doesn't seem to like the json column at all. Here is more about what I'm getting back:

[matth]

I've made some assumptions but something like this?

[jerry_onscreeninc.com]

That would be perfect but doesn't work on my data. I have a JSON object with other objects in it.
You have an array of objects.

[jerry_onscreeninc.com]

Ahh, as soon as I wrote it out....
{{ Object.keys(currentRow.participants).length}}

I thank you, but sorry to bother....