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Set the default PDF application to "Preview in Firefox" through a preferences file

  • 3 replies
  • 1 has this problem
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  • Last reply by chazbot7

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I work for a company that uses Firefox for Linux across hundreds of locations. Currently, we have all locations set to use Adobe Reader as the default PDF viewer. From what I can see, this changes the "plugin.disable_full_page_plugin_for_types" value to "" in prefs.js.

We'd like to set all locations to use the built in "Preview in Firefox" option. When looking at the prefs.js file, selecting this option changes the value of the above preference to "applications/pdf". However, this value applies to "Preview in Firefox" and "Save File". When I try to simply overwrite the prefs.js file at a location using that new value, it defaults to "Save File" rather than "Preview in Firefox".

Obviously, this value can be corrected in the GUI by selecting it in Preferences > Applications. However, to ensure we actually get all locations successfully switched over, we'd like a more controlled process that takes the users out of the equation. Is there another preferences file that controls the preferred application to use for file types that we can overwrite?

System specs: Linux - CentOS 5. Firefox v 38.2.0-4.el5.centos

Thanks in advance!

I work for a company that uses Firefox for Linux across hundreds of locations. Currently, we have all locations set to use Adobe Reader as the default PDF viewer. From what I can see, this changes the "plugin.disable_full_page_plugin_for_types" value to "" in prefs.js. We'd like to set all locations to use the built in "Preview in Firefox" option. When looking at the prefs.js file, selecting this option changes the value of the above preference to "applications/pdf". However, this value applies to "Preview in Firefox" and "Save File". When I try to simply overwrite the prefs.js file at a location using that new value, it defaults to "Save File" rather than "Preview in Firefox". Obviously, this value can be corrected in the GUI by selecting it in Preferences > Applications. However, to ensure we actually get all locations successfully switched over, we'd like a more controlled process that takes the users out of the equation. Is there another preferences file that controls the preferred application to use for file types that we can overwrite? System specs: Linux - CentOS 5. Firefox v 38.2.0-4.el5.centos Thanks in advance!

All Replies (3)

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I believe this is the same on Linux as on Windows: "download-handling preferences" are stored in the mimeTypes.rdf file, which is a difficult-to-read XML file in the user's profile folder. I don't know whether there is a convenient way to modify that file.

(By the way, it's not a good idea to overwrite prefs.js because it contains accumulated user data that can be difficult to restore, such as pinned tiles and blocked sites on the new tab page, toolbar layout, and other customization data.)

A good source on customization is Mike Kaply. For example:

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

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

pref("general.config.filename", "mozilla.cfg");
pref("general.config.obscure_value", 0);

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

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

See:

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@jscher2000 and @cor-el thank you for the help! It looks like there might be a few different ways to do this, I'll get crackin at it today. Mike Kaply's site is a huge help.