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How can I deploy the setting for the default PDF action back to Reader?

  • 4 replies
  • 7 have this problem
  • 5 views
  • Last reply by JasonNVSD

JasonNVSD
JasonNVSD
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Due to a legacy application, we must continue to use an old version of Reader with Firefox. Firefox 19 changes it to the built-in viewer, and once someone has upgraded, setting "pdfjs.disabled" to "true" changes the action to "Always ask" (not back to Reader). If I set it through Tools and Options, it only changes it for the current user.

I need to be able to apply to set this for all users, and preferably in a way that can be deployed to many machines.

Due to a legacy application, we must continue to use an old version of Reader with Firefox. Firefox 19 changes it to the built-in viewer, and once someone has upgraded, setting "pdfjs.disabled" to "true" changes the action to "Always ask" (not back to Reader). If I set it through Tools and Options, it only changes it for the current user. I need to be able to apply to set this for all users, and preferably in a way that can be deployed to many machines.

All Replies (4)

Andrew
Andrew
  • Moderator
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In order to change the default reader for PDF files (to not open PDF files with Firefox's internal PDF reader), follow these steps:

  1. Go to Tools > Options (or Firefox > Options).
  2. In the Options window, select the Applications tab.
  3. In the Search field, type PDF. You should find Portable Document Format (PDF).
  4. On the right handside you should find an Action column. Use that to select your favorite PDF reader. In order to view PDF files in Firefox, choose Preview in Firefox.
JasonNVSD
JasonNVSD Question owner
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That only changes it for the current user. I need to be able to change it for all users.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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You will probably have to parse the plugin.disable_full_page_plugin_for_types pref and remove "application/pdf" to make Firefox use the Adobe Reader for embedded PDF files.

See also:

The only way to modify prefs for all users is via a mozilla.cfg file because this file is run as a JavaScript file and can contain privileged JavaScript code.

You can use a mozilla.cfg file in the Firefox program folder to lock prefs or specify new (default) values.

Place a file local-settings.js in the defaults\pref folder where you also find the file channel-prefs.js to specify using mozilla.cfg. 

pref("general.config.filename", "mozilla.cfg");
pref("general.config.obscure_value", 0); // use this to disable the byte-shift

See:

These functions can be used in the mozilla.cfg file: 

defaultPref();  // set new default value
pref();         // set pref, but allow changes in current session
lockPref();     // lock pref, disallow changes

Modified by cor-el

JasonNVSD
JasonNVSD Question owner
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Thanks cor-el! I already use locked preferences, but I didn't know pdfjs added that one.

Is it possible to use locked preferences to always block "application/pdf" but allow other values that might be added in the future?