Function expectTextareaValueContains

expectTextareaValueContains(
    page: any,
    selectorKey: string,
    valueKey: string,
): Promise<void>
Asserts that a textarea element has a value containing the expected substring. Supports fixtures for reusable selectors and values.
Parameters
- page: any
- selectorKey: string
- valueKey: string
Returns Promise<void>
Example
```
Then I pw see textarea value "comments.textarea" contains "comment"
```
- Defined in backend/assertions/forms.ts:81