Add note about Cookies an JavaScript on cookie-params.md

docs/en/docs/tutorial/cookie-params.md

@@ -30,6 +30,16 @@ To declare cookies, you need to use `Cookie`, because otherwise the parameters w
 
 ///
 
+/// info
+
+Have in mind that, as **browsers handle cookies** in special ways and behind the scenes, they **don't** easily allow **JavaScript** to touch them.
+
+If you go to the **API docs UI** at `/docs` you will be able to see the **documentation** for cookies for your *path operations*.
+
+But even if you **fill the data** and click "Execute", because the docs UI works with **JavaScript**, the cookies won't be sent, and you will see an **error** message as if you didn't write any values.
+
+///
+
 ## Recap
 
 Declare cookies with `Cookie`, using the same common pattern as `Query` and `Path`.