Tabs focus

The tabs should not each have their own [tabindex="0"]. The order of focus should be:

1. before the tablist object
2. the set of tabs, where the tab with [aria-selected="true"] receives the focus
3. the corresponding panel
4. after the tablist object

Numbers 2 and 3 may be switched depending on the orientation of the tabs relative to the panel, e.g. if the tabs are on the bottom or to the right of the panel.

Tab activation

Use WAI-ARIA Authoring Practices to choose either automatic activation or manual activation. On macOS, for example, using the arrow keys switches the focus of tabs, but does not select them.

Use [aria-selected="true"] for selected tab, use :focus for focused. Remove [aria-expanded] attribute.