How to Enable Firefox Inbuilt PDF Viewer.


As you will aware Firefox has newest version Firefox 15.0 is live now. The new version comes with many previous bug fix and some new features.  One such feature is in built PDF viewer. This means you don’t require PDF viewers like Adobe Reader for viewing PDF files. Even though this is new feature added in Firefox with release of 15.0 versions this feature is in disabled state.

What Mozilla has stated is PDF viewer is still in beta stage and this is same reason it’s in dormant state . In this post I will explain you how to activate the same feature.

How to Active PDF Viewer on Firefox.

  1. Open Firefox and Type about:config in the address bar and press enter.
  2. This will open up a window saying “This might void your warranty”, click on the below button which says “I’ll be careful,I promise!”firefox-warranty
  3. From the next window type on the search bar “browser.pref” and find the entry which says “browser.preferences.incontent”.
  4. Double click on the entry to toggle the value from False to True.pdf-viewer-enable-on-firefox

That’s it, PDF viewer is now active.

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SK is the Founder of Techdunes. Loves blogging on Technology. Follow him on Twitter at @funmansk. Contact him at : admin(at)


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