React Testing Library Not Parsing JSON

Question

I have a TextArea component that takes JSON {"someKey": "someValue"}. When I inspect the dom, {"someKey": "someValue"} shows up just fine in the inspector.

However, when I try react testing library, RTL thinks the TextArea seems to contain "[object Object]" which isn't JSON parseable.

Any insight into

1. Why RTL is interpreting this json as "[object Object]"
2. How I can test it? I'd like to assert the value I typed in is there