I’ve talked to some folks here, poked around, and we believe it’s probably fine for `aspect-ratio` to override `-webkit-aspect` ratio. 

It looks like Chromium removed `-webkit-aspect`  in 2014 because the "property is parsed and stored on RenderStyle, but it's not used anywhere, i.e. it has no effect.” https://codereview.chromium.org/647723002

I don’t see any Author-facing feature here. There's nothing about it on CSS Tricks, nothing on MDN. My demo does nothing. Looks like aspectRatioNumerator and aspectRatioDenominator appear to be unused.

Jen

Jen Simmons
Web Technology Evangelist
Apple, Inc.

Hi,

I was looking into aspect-ratio and there is one thing Christian did not 
mention yet. There is an existing aspect-ratio implementation 
(https://bugs.webkit.org/show_bug.cgi?id=47738) that uses the property 
-webkit-aspect-ratio and seems replaced elements only. Probably 
aspect-ratio can override -webkit-aspect-ratio, anyway since this may 
influence the position I thought I should mention it.

Cheers,

Rob.

 >Hello,

 >I'd like to request an official position the aspect-ratio CSS
 >property, as both Gecko and Blink are currently implementing it, and
 >ideally we'd like to ship it soonish.

 >https://drafts.csswg.org/css-sizing-4/#aspect-ratio

 >https://docs.google.com/document/d/1VqD0mfkIDyCxQBrrvDw5wEbhXBsmEYIhk6ahiX_fvco/edit#

 >Thanks,
 >Christian