[csswg-drafts] [css-align] are there compatibility issues with replacing overconstraint rules from CSS2?

dbaron has just created a new issue for https://github.com/w3c/csswg-drafts:

== [css-align] are there compatibility issues with replacing overconstraint rules from CSS2? ==
The [rules for `justify-self` on blocks](https://drafts.csswg.org/css-align/#justify-block) and the [rules for `justify-self` on Absolutely-Positioned boxes](https://drafts.csswg.org/css-align/#justify-abspos) specify that they replace the overconstraint rules in CSS Level 2 with the rules for justify-self.  This replacement is *not* scoped to values other than `normal`.  I think that is *probably* a good thing.

However, one issue where the overconstraint rules have come up is the question of what `getComputedStyle()` returns for the used values of `margin` (for block) or offset (for abspos) properties.  My memory is that this generally hasn't been particularly conformant to a literal reading of the spec, but this may have changed.

I think it's worth investigating what implementations do for `getComputedStyle()` and margins, and then either:
* scoping this replacement to non-`normal` values (which in some sense would introduce inconsistency), or
* adding a note that this replacement is intentionally intended to include `normal` values as well, and therefore that the used values of margins (for blocks) or offsets (for abspos) are no longer expected to be adjusted for overconstraint.

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/1428 using your GitHub account

Received on Saturday, 20 May 2017 21:41:36 UTC