With a long list of files, scrolling on the filetree will scroll the main body of the page, and will only scroll the filetree list up by page header, and then stay there, hiding the end of the list.

Sources say that adding height: 100%; overflow-y: scroll; to ul.phui-list-view makes the scrolling work.

(Chrome 52 on Windows and Mac, and Safari 9 on Mac; Here and at 325e3b3ff3548832b70be6cd1f075cb460236f44)