I am happy to announce that Dolphin has a new view mode: Columns. Each column shows one folder. Select a folder and its content opens in the next column, so the path from the folder you opened down to your selection stays on screen. This layout is known as Miller columns, after Mark S. Miller, who created it in 1980.
That seems way more useful than the columns in my opinion. I don’t use Dolphin but it is good to know. Thank your for mentioning it.