[csswg-drafts] [css-multicol-1][css-flexbox-1][css-grid-1] Clarify that column-* properties only apply to block containers

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

== [css-multicol-1][css-flexbox-1][css-grid-1] Clarify that column-* properties only apply to block containers ==
Currently, the Flexbox and Grid specifications explicitly exclude the `column-*` properties from applying to [flex](https://drafts.csswg.org/css-flexbox/#flex-containers) or [grid containers](https://drafts.csswg.org/css-grid/#grid-container).

As discussed in #1352, those exclusions should be removed from Flexbox and Grid and Multi-column be updated to clarify that these properties only apply to block containers.

Sebastian

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/1364 using your GitHub account