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The native Firefox PDF viewer will not work.

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  • Last reply by DaleG

DaleG
DaleG
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PDFs will not open in the native Firefox PDF viewer. I've deleted the mimetypes.rdf file, re-initialized the plug-ins database by deleting pluginreg.dat, and reinstalled Firefox. Firefox 48.0, Mac OSX 10.11.6. It quit working a while ago after a Firefox update, and I've never been able to get it working again. When I to go Preferences - Applications - Content type = PDF file, there is no selection for pdf viewer. I've disabled the Adobe Acrobat NPAPI plug-in, which installs automatically with Adobe Acrobat Reader, because it doesn't work, which is a known issue. I tried the "PDF Browser Plugin 2.4.4", which works, but disabled it because I don't like its functionality. Help!

PDFs will not open in the native Firefox PDF viewer. I've deleted the mimetypes.rdf file, re-initialized the plug-ins database by deleting pluginreg.dat, and reinstalled Firefox. Firefox 48.0, Mac OSX 10.11.6. It quit working a while ago after a Firefox update, and I've never been able to get it working again. When I to go Preferences - Applications - Content type = PDF file, there is no selection for pdf viewer. I've disabled the Adobe Acrobat NPAPI plug-in, which installs automatically with Adobe Acrobat Reader, because it doesn't work, which is a known issue. I tried the "PDF Browser Plugin 2.4.4", which works, but disabled it because I don't like its functionality. Help!

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DaleG
DaleG Question owner
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I figured out a solution. 1) Enter about:config in Firefox browser 2) search for "pdfjs.disabled" and toggle it from "true" to "false" 3) restart Firefox 4) go to Preferences - Applications and scroll to "Portable Document Format (PDF)" and click 5) the selections should now include "preview in Firefox", select that 6) restart Firefox. Note that the solution did not work until I restarted Firefox again.

PDF Preview in Firefox now works for me. Happy happy!