I switched over from KeePassX and one difference that I noticed was how the search operates. In KeePassXC, if you start typing in the search bar, it only shows you results from whatever group is selected and its subgroups. In KeePassX, searching would always return results from your entire database which I find to be much more useful. I don't know if this difference is intentional or a bug (I'm running this on macOS), but it'd be nice if this could be configurable.