1. in the search field, it should be possible to search not only within the active tab but also within all open tabs (for example, with a corresponding checkbox to determine whether all tabs should be searched).
2. it should be possible to search in the history not only for the URL itself but for the entire website content. After all, who hasn't experienced this: You have read something, but can't remember where. But you still know approximately when it was. So it would make sense to be able to limit the time range accordingly, for example to be able to select the range on a timeline. In the background, Firefox would then presumably have to load and search all the pages that were visited in the said time interval and are no longer in the cache.