[whatwg] <dialog>'s position property

[Matt Falkenhagen]

Hello,

I'm trying to implement the positioning of <dialog> in WebKit and am
looking at the UA style sheet for dialog [1]. Is there a reason
position:absolute is used instead of fixed?

According to the spec, a non-anchored dialog is vertically centered in
the viewport by default. It seems this can be implemented using
position:fixed and setting the top property appropriately. The left:0
and right:0 rules also seem to make more sense for spanning the
viewport rather than the containing element.

For anchored dialogs, the UA style sheet's position property doesn't
seem to matter, as the property must compute to 'absoluted-anchored'.

The WebKit bug tracking this is:
https://bugs.webkit.org/show_bug.cgi?id=90670

Thanks,
Matt

[1] http://www.whatwg.org/specs/web-apps/current-work/#flow-content-1