According to the spec: https://compat.spec.whatwg.org/#css-media-queries-webkit-device-pixel-ratio And to the Chromium implementation: https://cs.chromium.org/chromium/src/third_party/blink/renderer/core/css/media_query_evaluator.cc?l=366&rcl=1d7328865bcf06a687aafc18ff95d55317030672 They're no different than resolution. In our implementation `resolution` does slightly different stuff. I think we should make them match.

According to the spec: https://compat.spec.whatwg.org/#css-media-queries-webkit-device-pixel-ratio And to the Chromium implementation: https://cs.chromium.org/chromium/src/third_party/blink/renderer/core/css/media_query_evaluator.cc?l=366&rcl=1d7328865bcf06a687aafc18ff95d55317030672 They're no different than resolution. In our implementation `resolution` does slightly different stuff. Given we still haven't shipped -webkit-device-pixel-ratio, making this match resolution looks better than the opposite.

Comment on attachment 9001876 [details] Make webkit device-pixel-ratio media queries a proper alias to resolution. Daniel Holbert [:dholbert] has approved the revision.

Pushed by emilio@crisal.io: https://hg.mozilla.org/integration/autoland/rev/b107fee86cba Make webkit device-pixel-ratio media queries a proper alias to resolution. r=dholbert

Pushed by emilio@crisal.io: https://hg.mozilla.org/integration/autoland/rev/0c82bae4916e No bug - Remove comment that is outdated since I fixed it in bug 1483808.