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Change firefox pac file address programmatically, when firefox is running.

  • 2 replies
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  • Last reply by meraj

meraj
meraj
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I want to change firefox pac file address programmatically, when firefix is running, when i change from firefox network setting windows it writes these settings to prefs.js, but the vice versa is not true, when I change pac file address in prefs.js (path: C:\Users\dell\AppData\Roaming\Mozilla\Firefox\Profiles\o5zvow94.default-1385547093552) when firefox is running, it does not change pac file address in firefox. I tried creating user.js, but it does nothing. Guide me please.(firefox version 29.0)

Thanx alot.

I want to change firefox pac file address programmatically, when firefix is running, when i change from firefox network setting windows it writes these settings to prefs.js, but the vice versa is not true, when I change pac file address in prefs.js (path: C:\Users\dell\AppData\Roaming\Mozilla\Firefox\Profiles\o5zvow94.default-1385547093552) when firefox is running, it does not change pac file address in firefox. I tried creating user.js, but it does nothing. Guide me please.(firefox version 29.0) Thanx alot.

All Replies (2)

cor-el
cor-el
  • Moderator
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You can't make change to the prefs.js file while Firefox is running.

There is a warning at the top of the prefs.js file: 

/* Do not edit this file.
 *
 * If you make changes to this file while the application is running,
 * the changes will be overwritten when the application exits.
 *
 * To make a manual change to preferences, you can visit the URL about:config
 */

The user.js file is only read once when you start a new session to initialize some prefs.

You would have to create an extension that reads a file on the hard drive at regular intervals and changes the pref and initialize the PAC file.

meraj
meraj Question owner
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Thank You, Problem is when I change the prefs.js file when firefox is running, the change does not reflect in the firefox network settings. How can I change pac file address when firefox is running, is there any temp file or database, where it write the settings, and when we let suppose open a network settings windows it reads from that temp location?