The good news is that since Firefox 15, PDF viewer support is part of the browser, but it is disabled by default, and for the time being, it’s up to you to turn it on.
Instructions
Update to the latest version of Firefox.
In the address bar, type about:config and press Enter. To continue click the I’ll be careful, I promise! button.
Next, in the search box type browser.preferences.inContent and press Enter. Once you see the value in the Preference Name list, double-click it to change the value of “false” to “true”.
Now once again, in the search box type pdfjs.disabled and press Enter. You’ll see that this value is set to “true”, double-click it to set it to “false”.
There is one last step. From the file menu, click Tools, then Options. Now, navigate through the Applications tab. Search for Portable Document Format (PDF) value and change its setting to Preview in Firefox.
That should do it! To test, go to your favorite search engine, do a search for a PDF file, click it and it should open up with Firefox. All content on this site is provided with no warranties, express or implied. Use any information at your own risk. Always backup of your device and files before making any changes. Privacy policy info.
