Improving Tab Navigation [CSS Working Group Wiki]

There have been a number of concerns raised with the current 'nav-index' property. This page is to document them and the resulting discussions, with the aim of addressing these issues in a future revision of the UI module.

External Issues To Be Incorporated

Extract issues from these and document here as subsections explicitly:

Scoping tab navigation indices, so that it can be used in complex pages.

More issues:

Should HTML specify something

HTML or CSS or both

Does nav-index belong in HTML or CSS or both?

Current thinking: likely both.

HTML already has tabindex (see previous).

CSS should specify nav-index because:

CSS3-UI already specifies directional nav-* properties
Any style sheet that explicitly specifies the 2 dimensional directional nav-* properties will likely want to also explicitly specify sequential navigation order as well.
Keeping both sequential and directional nav-* in the same style sheet will help them stay “in sync” across site changes etc.
- Or rather, having to do them separately in HTML vs CSS will likely cause them to get out of sync.

However, nav-index was in a CSS3-UI CR draft for MANY years and there was no implementation.

Thus only when there is a strong demonstration of implementer interest (2+ commitment to implement) should we consider adding it to CSS4-UI.

within a dialog and browsing context

We should define how to pick the next/previous element in sequential focus navigation, to make sure it's clear that it stays within a dialog and browsing context.

More details and follow-up:

contextual scoping

Need contextual scoping for sequential focus navigation.