Test Case Boilerplate
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HTML
<div class="test">
<p>Showcase of wrong calculation for large <strong>z-index</strong> values in FF>=5</p>
<p>Correct value should be <strong>1111112</strong></p>
</div>
<div class="test2">
<p>Showcase of even larger z-index value <strong>z-index</strong> values in FF>=5</p>
<p>Correct value should be <strong>11111112</strong></p>
</div>
CSS
.test {
z-index:1111112;
position:relative;
}
.test2 {
z-index:11111112;
position:relative;
}
p {margin-bottom:1em;}
div {margin-bottom:1.5em;}
JavaScript
var $el = $('.test'),
el = $el.get(0);
var computedZindex = document.defaultView.getComputedStyle(el , null ).getPropertyValue('z-index');
//not working in FF
//console.log('computedZindex ');
$el.append('Testing .getComputedStyle: '+computedZindex );
$el.append("</br>");
$el.append('Testing $.css: '+$el.css('z-index'));
$el.append("</br>");
$el.append('Testing parseInt() on z-index: '+parseInt(computedZindex ));
$el = $('.test2');
el = $el.get(0);
computedZindex = document.defaultView.getComputedStyle(el , null ).getPropertyValue('z-index');
$el.append('Testing .getComputedStyle: '+computedZindex );
$el.append("</br>");
$el.append('Testing $.css: '+$el.css('z-index'));
$el.append("</br>");
$el.append('Testing parseInt() on z-index: '+parseInt(computedZindex ));