It looks like there were independent `display-inside/outside` properties, with `display` being a "one property that sets multiple properties" shorthand, in the first draft of the spec:
> Changes since the 11 September 2014 Working Draft include:
> Removed `display-inside`, `display-outside`, and `display-extras` longhands, in favor of just making `display` multi-value. (This was done to impose constraints on what can be combined. Future levels of this specification may relax some or all of those restrictions if they become unnecessary or unwanted.)
But I'm stoked to even see these orthogonal axes and their domains officially laid out, and names given to concepts. Even just `display-inside` vs `display-outside`.
I've had discussions with professionals where no one was certain enough about the `display` mess to make any confident statements on the exact nature of the similarity between `flex` and `block`. Who knew if there were edge cases that made them not have (what I now have the words to describe as) the same `display-outside` behaviour? Thanks also to the crazy muddle of just-slightly-different behaviour the proliferation of other display options has scarred us all with, previously all sharing a single, very arbitrary-seeming, axis.
https://www.w3.org/TR/2014/WD-css-display-3-20140911/#the-di...
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But that has since been changed to `display` being a "one property that takes multiple values" shorthand, in the current version of the spec:
https://www.w3.org/TR/2015/WD-css-display-3-20150721/#change...
> Changes since the 11 September 2014 Working Draft include:
> Removed `display-inside`, `display-outside`, and `display-extras` longhands, in favor of just making `display` multi-value. (This was done to impose constraints on what can be combined. Future levels of this specification may relax some or all of those restrictions if they become unnecessary or unwanted.)
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But you're right. It's not even on caniuse yet (vote here: https://github.com/Fyrd/caniuse/issues/2337).
But I'm stoked to even see these orthogonal axes and their domains officially laid out, and names given to concepts. Even just `display-inside` vs `display-outside`.
I've had discussions with professionals where no one was certain enough about the `display` mess to make any confident statements on the exact nature of the similarity between `flex` and `block`. Who knew if there were edge cases that made them not have (what I now have the words to describe as) the same `display-outside` behaviour? Thanks also to the crazy muddle of just-slightly-different behaviour the proliferation of other display options has scarred us all with, previously all sharing a single, very arbitrary-seeming, axis.