Sometimes, new files don't appear in Dolphin. A "refresh" option in the context menu would be useful.
I'm not arguing for or against having refresh in the context menu, but just to make sure you are aware: you can currently refresh by pressing F5, going to menu View, Refresh, or adding a Refresh button to the toolbar using menu, Settings, Configure Toolbars.
+1 for adding back in the refresh icon by default. It was one of the first things I had to look up when I recently switched to KDE. My understanding is that it was removed a while ago to clean up the interface but I think it's still very important today as there are cases where refreshing is sometimes required (network locations). I've also encountered some graphical bugs which requires a refresh to clear up, so I end up clicking the button fairly frequently.
may i shameless recommend and point you to: https://store.kde.org/p/1734582