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Help using about:config to delete form info on shutdown. Value set to true but forms still autocomplete, need to do for 1500 devices

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  • Last reply by cor-el

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So I have deployed firefox 46 to 1500 devices, I have locked some of the preferences in mozillia.config. I don't want it to remember any form data, history etc. In the about:config I have set the privacy.clearonshutdown to true for cache , cookies, downloads, formdata and history but when firefox reopens the data is still there

What am I doing wrong. I need to make the changed via a config file so I can deploy to all machine

So I have deployed firefox 46 to 1500 devices, I have locked some of the preferences in mozillia.config. I don't want it to remember any form data, history etc. In the about:config I have set the privacy.clearonshutdown to true for cache , cookies, downloads, formdata and history but when firefox reopens the data is still there What am I doing wrong. I need to make the changed via a config file so I can deploy to all machine

All Replies (10)

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For additional info I have added the below to my Mozilla config file and have checked it is all in the about config . However if I go into firefox options and look at the setting not only are they not changed but not locked either

//Ensure form data is removed and not cached lockPref("privacy.clearOnShutdown.formdata", true); lockPref("privacy.clearOnShutdown.cache", true); lockPref("privacy.clearOnShutdown.cookies", true); lockPref("privacy.clearOnShutdown.downloads", true); lockPref("privacy.clearOnShutdown.history", true);

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Did you create a local-settings.js file in the correct location?

A local-settings.js file needs to be placed 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

The mozilla.cfg file needs to start with a comment line (//).

See Configuration:

See also:

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Yes Cor-el my local setting is set as above

as I mentioned above you can see that the config is being referenced as when I got into the about:config you can see the changes in italic. However if I go into the options, privacy settings and change firefox will : use custom settings for history all of those tick boxes are still ticked and can be changed

Im thinking maybe I might be locking down the wrong things ??

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Do you have privacy.sanitize.sanitizeOnShutdown = true? That's the "master switch" corresponding to the "Clear history when Firefox closes" checkbox on the Privacy panel of the Options page.

Do you also want to disable form and search autocomplete so that new data isn't stored? browser.formfill.enable = false

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many thanks I did find those switches

however I found a bit of a cheat

what i ultimately decided to do was force private browsing and lock it down.

that way it doesn't save any details. Also from a new user opening up firefox gives them a nice new clean feel every time it is opened

Thanks for the help though guys

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Are you leaving Tracking Protection enabled? It can break some site features, so that might be a support issue. See: What happened to Tracking Protection?.

Modified by jscher2000 - Support Volunteer

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So if I wanted private browsing on but tracking protection disabled what switches would I need ?

Ultimately what I want to achieve is a nice clean looking firefox everytime it is opened with no history and no sign of remember form or user history

This machine can be accessed by members of public although can only get to certain sites controlled by a pac file

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Sorry guys thought this was fixed but the privacy browsing stopped other functionality

I added the line

lockPref("privacy.sanitize.sanitizeOnShutdown ", true);

but this still seems to be keep the info in the username form field when you go to type it in again

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Smiler_cov said

I added the line

lockPref("privacy.sanitize.sanitizeOnShutdown ", true);

but this still seems to be keep the info in the username form field when you go to type it in again

Is it pre-filled in the form when you load the page, or does it appear in a drop-down below the field when you start typing? Form history generally appears in a drop-down. Data pre-filled in a field could remain from cache, or could be sent by the server (or filled by JavaScript) based on a cookie.

Or the Password Manager?

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Note that when you reopen tabs automatically then a lot of website related data is stored in sessionstore.js as part of the session data. This includes form data and cookies.