URL: https://itunes.apple.com/us/app/mindix/id595081194?l=en&ls=1&mt=12

Browser / Version: Firefox 57.0
Operating System: Mac OS X 10.11
Tested Another Browser: Yes

Problem type: Design is broken
Description: Button very blurry in Firefox
Steps to Reproduce:
Design is "broken" is a bit exaggerated - it seems there is a media query with the proprietary -webkit-min-device-pixel-ratio, but missing a min-resolution addition.

In the file https://s.mzstatic.com/htmlResources/9c33d3e/web-storefront-macpreview.css, instead of

@media only screen and (-webkit-min-device-pixel-ratio: 2) {
    background-image: url(web-storefront/images/view_in_macappstore@2x/viewinmacappstore_en@2x.png)
}

the media query should be changed to:

@media only screen and (min-resolution: 2dppx), only screen and (-webkit-min-device-pixel-ratio: 2){}

Tested: https://codepen.io/scheinercc/pen/dzdELw?editors=0100#0
(see also https://css-tricks.com/snippets/css/retina-display-media-query/)

edits: remove obsolete brackets; highlight code

layout.css.servo.enabled: true

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