[whatwg] HTMLForms: Implicit Submission with {display:none} button

[Ryosuke Niwa]

FYI, I checked Firefox 5's & Internet Explorer 9's behaviors as well.

IE9 does implicit submission in the following conditions:

   - One text field
   - One text field with one visible submit button
   - One text field with one display:none submit button
   - Two text fields with one visible submit button

It does not do implicit submissio in the following conditions:

   - Two text fields
   - Two text fields with one visibility:hidden submit button
   - Two text fields with one display:none submit button

Basically, IE9 only does implicit submission when there is exactly one text
field (you can have checkbox, hidden, etc...) or there is a visible button
(i.e. not diplay: none nor visibility: hidden).

Firefox 5 does implicit submission in the following conditions:

   - One text field
   - One text field with one visible submit button
   - One text field with one display:none submit button
   - Two text fields with one visible submit button
   - Two text fields with one visibility:hidden submit button
   - Two text fields with one display:none submit button

It does not do implicit submissio in the following conditions:

   - Two text fields

In summary, Firefox special cases one text field (can have checkbox, hidden,
etc...) like MSIE and requires a submit button with more than two text
fields regardless of presence of visibility: hidden or display: none.