Enable submitting when RETURN is pressed on first input

The form is submitting only when pressing enter on the second input or clicking Save.

Thanks in advance

You expect it to close on enter from the first field or jump to the next field?

I’d expect it to submit the form like every other form on the web. Here is what the HTML5 Specification says about this topic:

If the user agent supports letting the user submit a form implicitly (for example, on some platforms hitting the “enter” key while a text field is focused implicitly submits the form), then doing so for a form whose default button has a defined activation behaviour must cause the user agent to run synthetic click activation steps on that default button.

You can read more here: HTML Standard