Firefox does not open PDF files in browser. You would need to use a plug-in such as pdf viewer to be able to read PDFs in browser. Some of these plug-ins may be buggy and spammy however. ALternatively, you can save, download and open the PDF from the link in the browser to your hard drive and then open. Otherwise, it is recommended that if you really want to read PDF files in browser, to use Safari or Chrome, both of which do open PDFs in browser.
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The latest version of Firefox opens PDFs natively. These are the instructions on how to update Firefox.
Update Firefox to the latest version
By default, Firefox is set to automatically update itself but you can always do a manual update. Here's how:
- On the menu bar click the menu and select .
- The About Firefox window will open and Firefox will begin checking for updates and downloading them automatically.
- When the updates are ready to be installed, click .
If the update didn't work for some reason, just download and install a fresh copy.