I haven't been able to reproduce this yet, but I received a report of this on Twitter and another via email, which suggests it's not isolated to one system.
Bug 1714212 Comment 2 Edit History
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I haven't been able to reproduce this yet, but I received a report of this on Twitter and another via email (as well as the reporter's comment that others have flagged this issue on the NVDA users group), which suggests it's not isolated to one system.