This page contains the issues that are not yet listed in the specification and the resolutions for issues that were in the spec. but got resolved.

Link to current Working Draft:http://www.w3.org/TR/css3-grid-layout/

Link to current Editor's draft: http://dev.w3.org/csswg/css3-grid-align/

Grid-layer vs. z-index property for Grid

Grid-layer is currently used to control the stacking of grid items in a grid element; one example of this would be using Grid to build a range control where the “thumb” of the control is displayed on top of the underlying track. However, grid-layer is in many ways similar to the existing z-index property. Is a separate property needed, or can z-index replace the grid-layer property?

Z-index should be used to replace the grid-layer property. Specifically, in cases where Grid Items overlap, z-index provides control over the drawing order of Grid Items. Both Grid elements and Grid Items generate a stacking context as described for floats (step 5, section 14) in the CSS3 Box Model. Note that this would imply that z-index applies to statically positioned Grid Items.

Note also that this change has been previously discussed on the www-styling mailing list.

Fractional-track sizing algorithm update

The grid-sizing algorithm introduced in the previous Editor's Draft did not define the expected behavior for sizing a fractionally-sized track (e.g. 1fr, 2fr,…) when a Grid Element was shrink-to-fit. This should be addressed so that future implementations of Grid Layout behave predictably across platforms.

We propose to modify the existing grid sizing algorithm as follows: if the Grid Element is shrink-to-fit, then the algorithm follows its current path. However, if the Grid Element is not shrink-to-fit, then we set the size of a fractional track (i.e. determine the size of a '1fr' track) by making sure that 1) the proportions of all fractional tracks are preserved (e.g. a '1fr' track is half the size of a '2fr' track) and 2) fractional tracks are large enough contain all Grid Items that span them. The specific algorithm updates can be found in step 6 of the updated Editor's Draft.