CSS3 Values and Units defines a 'dppx' unit for <resolution>.
This bug is for implementing it.
Note: This would implement the same functionality as the non-standard 'device-pixel-ratio' query added in bug 474356.
Note that there's currently a discussion about renaming 'dppx' to just 'x':
Created attachment 639544 [details] [diff] [review]
goes on top of bug 771390
Basically passed try (though a few Windows tests still pending):
try: --build d --platform linux,macosx64,win32,android --unittests all --talos none --no-emails
Comment on attachment 639544 [details] [diff] [review]
I've updated: https://developer-new.mozilla.org/en-US/docs/CSS/Resolution who describes the <resolution> data type
(For the moment, until Kuma goes live in a few days, it isn't visible on the main wiki, only via the link given — later remove -new from the URL)
Can you also update our page on 'device-pixel-ratio' to show 'resolution: Ndppx' as the standardized alternative?
I've indicate the info on -moz-device-pixel-ratio in https://developer-new.mozilla.org/en-US/docs/CSS/Media_queries (with a link to your CSSWG article)
Thanks for the hint. It was clearly needed.
I've update the |resolution| section too.