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Cannot view PDF files in Firefox

  • 3 cavab
  • 1 has this problem
  • 47 views
  • Last reply by WestEnd

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I can not open PDF files within Firefox, nor can I open them in an external program like Adobe Acrobat Reader. They automatically save to my Downloads folder instead. I have already changed the settings for "Portable Document Format (PDF)" under Options > General > Applications to be "Preview in Firefox" and I have also tried changing it to "Use Adobe Acrobat Reader DC". Neither seem to be working. It still downloads the file instead of opening it. I have also verified that there are no extensions that may be affecting the way the setting behaves, and there is nothing.

I can not open PDF files within Firefox, nor can I open them in an external program like Adobe Acrobat Reader. They automatically save to my Downloads folder instead. I have already changed the settings for "Portable Document Format (PDF)" under Options > General > Applications to be "Preview in Firefox" and I have also tried changing it to "Use Adobe Acrobat Reader DC". Neither seem to be working. It still downloads the file instead of opening it. I have also verified that there are no extensions that may be affecting the way the setting behaves, and there is nothing.

All Replies (3)

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So what site is this that is causing the problem?

Modified by WestEnd

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I figured it out. There was a hidden add-on that was affecting it, but it wasn't showing in the add-ons list

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Addons not showing would mean malware is my sense.

Modified by WestEnd