Why are forms not submitted if there is more than one unnamed input?

Question

<form method="POST" action="">
    <input type="text" />
    <input type="text" />
</form>

( JSFiddle )

Press enter on input. Then delete one of inputand click it again. When we have two inputs inside the form, the form does not appear (we need a button). Why is this?

Answer 1

The default behavior of single-entry HTML forms is to submit. Once you add a second input, pressing the enter button will no longer submit the form. The presence or absence of names has nothing to do with it.

Answer 2

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Answer 3

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