Interactive tree: slightly larger boxes; a little more “white space” round the content; and the ‘root’ individual highlighted in bold.
Also, one of the images on the page shows the intended result.
Unfortunately those changes didn’t make it into the final release. They will be included in 3.3.9 when that is available, but that’s not likely to be any time soon.
If you would like to have this, purely cosmetic, improvement now, just download the zip folder attached to this post, extract the file ‘treeview.css’ and upload it your your web server, replacing the file of the same name in the folder kiwitrees/modules_v4/tree/css/ .