Because of missing alternatives the Acrobat Reader was always my preferred application for embedded viewing of pdfs in Firefox. But now I use Okularplugin – a lightweight browser plugin that is intended for replacing Adobe’s Acrobat Reader.

Okularplugin integrates okular directly into Firefox (and Chrome and Opera). Here are some screenshots:

Okularplugin was initially created by jeremysanders. But looks like he is no longer interested in maintaining it, so I adopted it and improved many things since then. For example I optimized the layout for viewing in web browsers. Okularplugin is a plugin for NPAPI-compatible browsers. This means it works with Mozilla Firefox, Google Chrome / Chromium and Opera. Try it out yourself!

You can find the project page on GitHub: Okularplugin on GitHub

UPDATE: Version 1.0.0 is available. See “okularplugin 1.0.0 released” for more details.

Installation Instructions

(See Okularplugin on GitHub for the up-to-date version.)

Install dependencies:

$ sudo apt-get install gcc automoc cmake kdelibs5-dev

Congrats! Nothing to do for you, continue to “Download & compile source”.

Download & compile source:

$ git clone
$ cd okularplugin
$ mkdir build
$ cd build
$ cmake ..
$ make
$ sudo make install

Activate Plugin:

Firefox (32Bit and 64Bit):
$ mkdir -p ${HOME}/.mozilla/plugins
$ ln -s /usr/lib/ ${HOME}/.mozilla/plugins
Chromium (32Bit and 64Bit):
$ sudo mkdir /usr/lib/chromium-browser/plugins
$ sudo ln -s /usr/lib/ /usr/lib/chromium-browser/plugins
Chrome (32Bit and 64Bit):
$ sudo mkdir /opt/google/chrome/plugins
$ sudo ln -s /usr/lib/ /opt/google/chrome/plugins