In bug 1122918, we implemented these keywords, but they're preffed off for release channels (except on B2G) because it wasn't clear how stable the spec is... in particular, should the values be 'inline-start' and 'inline-end' or simply 'start' and 'end'? Attempts to ask the CSSWG for clarification led to extensive discussion, but I don't recall a clear resolution emerging. Both [1] and [2] currently have the 'inline-*' forms, matching what we landed in bug 1122918, but it's also still flagged as an open issue in [1]. [1] https://drafts.csswg.org/css-logical-props/#float-clear [2] https://drafts.csswg.org/css-page-floats/#float-property

Elika (as one of the editors of logical-props), do you have any sense of where this stands?

Discussed a little at this week's CSS WG teleconference, but will try to revisit more seriously next week.

Since I've landed few patches to Firefox that use these keywords, and there doesn't seems to be any progress in the last half a year, is there any progress? If not, is it possible to implement this as a prefixed -moz- keywords even if restricted to the browser chrome?

The CSS WG just made a decision on this, noted at https://log.csswg.org/irc.w3.org/css/2017-04-20/#e800353. The spec[1] will no doubt be updated soon to resolve the open issue, and as this decision matches what we implemented, I think we can now move forward with shipping these values across all channels. [1] https://drafts.csswg.org/css-logical-props/#float-clear

This just makes the pref default to enabled everywhere; once we've done this, assuming nothing unexpectedly breaks, we can follow up fairly soon with a patch to remove the pref completely.

Filed bug 1358450 about removing the pref. By keeping this bug to the minimal pref-flipping patch, rather than the actual code removal, perhaps we can even consider uplifting it to ship sooner, so that front-end code will be free to start using these values (as per comment 3).

https://hg.mozilla.org/integration/mozilla-inbound/rev/024606c3a9503ace4c89f5aba6ddf01dd5db6ee9 Bug 1253919 - Enable support for the logical values of CSS 'float' and 'clear' properties for all channels. r=dbaron

I've updated the browser supporting information on the ref pages: https://developer.mozilla.org/en-US/docs/Web/CSS/float https://developer.mozilla.org/en-US/docs/Web/CSS/clear Removed the entry from the experimental features page: https://developer.mozilla.org/en-US/Firefox/Experimental_features And added an entry to the Fx55 release notes: https://developer.mozilla.org/en-US/Firefox/Releases/55#CSS I think that covers it; let me know if you think anything else is needed. Thanks!