The history UI fetches history entries by issues multiple requests to the BrowsingHistoryService, each request returning ~100 entries. If a day has more than 100 history entries, then it will take multiple requests to get the full days worth of history.

However, our deduplication logic lives inside BrowsingHistoryService and backing local history logic. And right now, we are not able to dedupe at all across these paging requests. So the same URL can appear multiple times for the same day, when our

This creates a really inconsistent experience for the user, where sometimes their history seems to be condensing/deduping results and sometimes it is not.

This issue is closely related to crbug.com/759803