I filed a companion bug to this bug as bug 1904430. When testing, it appears there is no way for a TalkBack user to know the current tab. This information is conveyed visually through the purple ring around the current tab, but not conveyed in TalkBack.
Bug 1813616 Comment 6 Edit History
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I filed a companion bug to this bug as bug 1904430. When testing, it appears there is no way for a TalkBack user to know the current tab. This information is conveyed visually through the purple ring around the current tab, but not conveyed in TalkBack. (Not related to moving focus, but impacting the same user experience.)