Install kpartsplugin by entering the following commands in the terminal:
sudo apt update sudo apt install kpartsplugin
Description:
Netscape-compatible plugin to embed KDE file-viewers into browser
This software implements a plugin for Netscape-compatible browsers in Unix environments. This plugin uses KDE's KParts technology to embed file viewers (e.g. for PDF files) into non-KDE browsers. Tested browsers include both (Mozilla Firefox and Opera, and is know to work with Chrome and Arora. With this plugin, you can e.g. view PDF files in Firefox using Okular as an embedded plugin.
Homepage: http://www.unix-ag.uni-kl.de/~fischer/kpartsplugin/
Version: 20120605-1
Section: universe/kde