Add a bunch of data to a URL data entry loacation

Yes. I made the mistake of expecting you to understand what this means:

A reference to a Text Object (which is what you’re trying to use) is not a CSS selector.

You can use the browser’s DevTools to help you build a selector.

It will be a string which might look something like this:

div.someclass textarea.anotherclass

If you’re lucky, it might have an id something like…

#expressions-text

If you have trouble, post your HTML showing that textarea and I’ll try to make one for you.