In this example: https://www.w3.org/WAI/ARIA/apg/patterns/tabs/examples/tabs-actions/#ex_label
Ii you move focus to an inactive tab after the active one, then press Shift+Tab, focus goes to the menu button associated with the active-tab.

The keyboard support table, for Shift+Tab says:

• When focus moves into the tablist, places focus on the menu button associated with the active tab.
• When focus is on the menu button associated with a tab, places focus on that tab.
• When focus is on a tab, moves focus to one of the following depending on which is nearest in the backward tab sequence:
  • The active tab.
  • The first focusable element preceding the tablist.

As I interpret it, the table says to move focus to the active tab, not its button. Which one is right?