I tested this with NVDA. When scrolling using Page Down, sometimes instead of announcing the message NVDA will announce "List." If I continue to use Page Down after hearing "List," nothing is announced, though visually I moving down through the list.
Bug 1819276 Comment 5 Edit History
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I tested this with NVDA on Windows 11. When scrolling using Page Down, sometimes instead of announcing the message NVDA will announce "List." If I continue to use Page Down after hearing "List," nothing is announced, though visually I moving down through the list.