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Adobe Reader installs the "Adobe Acrobat NPAPI Plug-in" for viewing PDF files inside your browser. If you use this plugin in Firefox, PDF files may be blank or you may see the message, Adobe Reader cannot show documents in this browser. We'll explain how to fix that.
- If you are having problems viewing PDF files with the built-in Firefox PDF Viewer, see instead Troubleshoot problems with the PDF viewer.
In order to view PDF files again, follow these steps:
- Click the menu button and select .
- Select the panel.
- Type pdf into the search bar.
- For each content type listed, click on the drop-down menu in the Action column.
- Change the selection to another action, such as Preview in Firefox or Use Preview.
- Close the Preferences window.