dolphin4 software package provides file browser, you can install in your Ubuntu 16.04 LTS (Xenial Xerus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install dolphin4
dolphin4 is installed in your system.
Make ensure the dolphin4 package were installed using the commands given below,
$ sudo dpkg-query -l | grep dolphin4 *
You will get with dolphin4 package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | KDE |
| Package | dolphin4 |
| Version | 4:15.12.3-0ubuntu1 |
| Description | file browser |
| Sub Section | KDE |