Created attachment 628303 [details]
User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_4) AppleWebKit/536.5 (KHTML, like Gecko) Chrome/19.0.1084.52 Safari/536.5
Steps to reproduce:
When a form control's label is hidden off screen, Firefox exposes Null as accessible name for the control. This seems to be occur whenever the label is styled with position:absolute; and overflow:hidden; (even if the label itself is still visible on the screen). If either the position or overflow CSS property is removed, the problem no longer occurs. Only when both position:absolute and overflow:hidden are set.
The attached test case demonstrates this issue (HTML code shown below).
<title>Test Case for label bug </title>
<h1>Test case for label issue</h1>
<label class="element-invisible" for="sampleTxt1">A hidden label</label>
<br /><br />
<input type="text" id="sampleTxt1" />
The label's styles should have no effect on the accessible name of the associated form control (especially since position and overflow are often used to hide content off screen).
It seems that the label is no longer considered an accessible object once the position and overflow style are set.
This is blocking web developers from using sanctioned techniques to apply more context information for screen reader users. Read here:
Alex, can you take a look please?
*** This bug has been marked as a duplicate of bug 501580 ***