View PDF files in Firefox or choose another viewer

Revision Information
  • Revision id: 36985
  • Created:
  • Creator: philipp
  • Comment: in firefox 19 "portable document format (pdf)" has to be changed to use a third party PDF plugin to work in firefox
  • Reviewed: Yes
  • Reviewed:
  • Reviewed by: AliceWyman
  • Is approved? Yes
  • Is current revision? No
  • Ready for localization: No
Revision Source
Revision Content

To display PDF files inside the Firefox browser window, you can use the built-in PDF Viewer or a PDF reader plugin. This article covers both methods and how to fix the common issues you might encounter.

To display PDF files inside the Firefox browser window, you can use the PDF Viewer extension or a PDF reader plugin. This article covers both methods and how to fix the common issues you might encounter.

Using the built-in PDF Viewer

Firefox now includes a built-in PDF viewer that allows you to view almost all PDF files found on the web without a plugin.

Note: This extension is still in Beta phase. If you are not comfortable with that, you should instead consider using a PDF reader plugin and skip down to this section.

PDF Viewer (aka pdf.js) is a new revolutionary extension using web standard technologies that allows you to display within Firefox almost all PDF files found on the web without a plugin.

PDF JS
The PDF viewer works automatically unless you've installed a PDF reader plugin like Adobe Reader. In that case you'll have to disable any PDF reader plugins before the built-in PDF viewer will work.

  1. Click the menu button Fx89menuButton, click Add-ons and themes and select Plugins.
  2. Select each PDF reader plugin and click Disable close to it.

Troubleshoot problems with the PDF viewer

Some PDF files don't render well or are blank

With certain types of PDF files, the PDF Viewer may have problems displaying fonts, colors or the whole document. To view these files:

  • Click the download button on the right side of the document header in order to open it with the default PDF program on your computer.

Cannot open any PDF files

Some extensions that block JavaScript may prevent PDF Viewer from working. You can disable them to allow PDF viewer to work:

  1. Click the menu button Fx89menuButton, click Add-ons and themes and select Extensions.
  2. Select each blocking extension and click Disable close to it.

For more information, see Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems.

Using a PDF reader plugin

If you can't deal with the PDF Viewer problems, you can still use PDF reader plugins like Adobe Reader, Nitro PDF Reader or Sumatra PDFAdobe Reader, MozPlugger, or KParts pluginSchubert|it PDF Browser Plugin on Mac OS X 10.6 and later.

PDF files are blank and can't be downloaded

See PDF files are blank or cause an error message on Mac.

Only the first page is visible (Mac 10.5 and below)

If PDF documents open within Firefox but only the first page is viewable, make sure that the QuickTime plugin isn't set to handle PDF content:

  1. From the Apple menu, choose System Preferences.
  2. From the View menu, choose QuickTime.
  3. Click the Plug-In tab and click MIME settings....
  4. In the list of MIME types, click the triangle next to "Images - Still image files".
  5. If "PDF Image" is checked, click the check box to clear it.
  6. Click OK

If you can't view a PDF in Firefox, continue with the next following instructions.

PDF files show up in the built-in PDF Viewer or are downloaded

Check Firefox settings

  1. In the Menu bar at the top of the screen, click Firefox and then select Preferences or Settings, depending on your macOS version.Click the menu button Fx89menuButton and select Settings.
  2. Select the Applications panel.
  3. Find Portable Document Format (PDF) in the list and click on it to select it.
  4. Click on the drop-down arrow in the Action column for the above entry and select Use PDF reader name (in Firefox).
    Opening PDF - Win v2
    • If Use PDF reader name (in Firefox) is not listed as an Option, see Reset download actions below and then repeat this set of instructions.
  5. Close the Settings page. Any changes you've made will automatically be saved.

If you still can't view a PDF in Firefox, continue with the following instructions.

Reset download actions

  1. Open your profile folder:

    • Click the menu button Fx89menuButton, click Help and select More Troubleshooting Information.From the Help menu, select More Troubleshooting Information. The Troubleshooting Information tab will open.
    • Under the Application Basics section next to Profile FolderDirectory, click Open FolderShow in FinderOpen Directory. A window will open that contains your profile folder.Your profile folder will open.
    Note: If you are unable to open or use Firefox, follow the instructions in Finding your profile without opening Firefox.

  2. Click the Firefox menu Fx89menuButton and select Exit.Click the Firefox menu at the top of the screen and select Quit Firefox.Click the Firefox menu Fx89menuButton and select Quit.
  3. Delete the mimetypes.rdf file.

Check Application settings

If the PDF reader plugin comes bundled with a reader application, check the application plugin setting if there is some.

  • Adobe Reader:
    1. Open Adobe Reader.
    2. Once in Adobe Reader, click the Edit menu in the menu bar, and then click Preferences... The Preferences window will open.
    3. In the Categories section, click on Internet.
    4. Make sure the first check box, Display PDF in browser, is checked.
    5. Click OK to dismiss the Preferences window, and then close Adobe Reader.

If you still can't view a PDF in Firefox, continue with the next following instructions.

Re-initialize the plugins database

Follow the instructions in Re-initializing the plugins database.

This will force Firefox to rebuild its plugin database. If you still can't view a PDF in Firefox, continue with the next following instructions.

Re-install the application

If the PDF reader plugin comes bundled with a reader application and the above troubleshooting methods for Firefox did not work, uninstall and re-install the application.

If you still can't view a PDF in Firefox, continue with the next following instructions.

Further information for Adobe Reader

If none of the above troubleshooting methods worked, see Can't view PDF on the web from Adobe.com for further instructions.