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Need help with some about:config settings

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Réiteach roghnaithe

Hey, check this out:

While viewing the Settings page, call up the Dev Tools using Ctrl+Shift+i

In the panel that opens, make sure you are displaying the 'Inspector panel, which shows a tree structured view of the HTML of the page.

Next, at the upper left corner of the panel, you'll see a button to select an element in the page by clicking. After you select the element, check the HTML for a preference attribute telling you exactly what it changes in about:config. Of course, for complex preference values, or changes that affect multiple preferences simultaneously, this won't be so helpful, but it's great for the true-false ones.

Example for your autoscrolling preference:

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How can we help?

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Réiteach Roghnaithe

Hey, check this out:

While viewing the Settings page, call up the Dev Tools using Ctrl+Shift+i

In the panel that opens, make sure you are displaying the 'Inspector panel, which shows a tree structured view of the HTML of the page.

Next, at the upper left corner of the panel, you'll see a button to select an element in the page by clicking. After you select the element, check the HTML for a preference attribute telling you exactly what it changes in about:config. Of course, for complex preference values, or changes that affect multiple preferences simultaneously, this won't be so helpful, but it's great for the true-false ones.

Example for your autoscrolling preference:

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Thank you jscher200, very helpful. Didn't know about that (not familiar with dev console.)

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Now normally when looking for a setting as you said ill have to look out for preference. What if that term is nowhere to be found? screenshot below.

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The popups are embedded/framed documents, so you need to use an extra trick. Use the frame selector to switch between inspecting the main page and the framed document(s).

In case you're curious about the other buttons:

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Thanks for the help, appreciate it. Having diffculty time figuring this out.

Could you take a look at the screenshot? DoH networkttr mode i set to 2 and lockPref, then why if lockpref is active can it be edited? Are there conflicts? Browser reports no errors.

Here the config:

//start lockPref("librewolf.cfg.version", "6.0"); lockPref("browser.contentblocking.category", "strict"); lockPref("network.cookie.cookieBehavior", 5); // enforce dFPI lockPref("privacy.partition.serviceWorkers", true); // isolate service workers lockPref("network.cookie.lifetimePolicy", 2); // keep cookies until end of the session, then clear lockPref("network.cookie.thirdparty.sessionOnly", true); lockPref("network.cookie.thirdparty.nonsecureSessionOnly", true); lockPref("privacy.clearOnShutdown.cookies", false); lockPref("privacy.sanitize.sanitizeOnShutdown", true); lockPref("privacy.sanitize.timeSpan", 0); lockPref("browser.cache.disk.enable", false); // disable disk cache lockPref("browser.privatebrowsing.forceMediaMemoryCache", true); lockPref("media.memory_cache_max_size", 65536); lockPref("browser.shell.shortcutFavicons", false); lockPref("browser.pagethumbnails.capturing_disabled", true); lockPref("browser.helperApps.deleteTempFileOnExit", true); // delete temporary files opened with external apps lockPref("privacy.history.custom", true); lockPref("browser.privatebrowsing.autostart", false); lockPref("browser.formfill.enable", false); // disable form history lockPref("browser.sessionstore.privacy_level", 2); // prevent websites from storing session data like cookies and forms lockPref("browser.sessionstore.interval", 60000); // increase time between session saves lockPref("privacy.query_stripping.enabled", true); lockPref("privacy.query_stripping.strip_list", "__hsfp __hssc __hstc __s _hsenc _openstat dclid fbclid gbraid gclid hsCtaTracking igshid mc_eid ml_subscriber ml_subscriber_hash msclkid oly_anon_id oly_enc_id rb_clickid s_cid twclid vero_conv vero_id wbraid wickedid yclid"); lockPref("librewolf.uBO.assetsBootstrapLocation", "https://gitlab.com/librewolf-community/browser/source/-/raw/main/assets/uBOAssets.json"); lockPref("dom.security.https_only_mode", true); // only allow https in all windows, including private browsing lockPref("network.auth.subresource-http-auth-allow", 1); // block HTTP authentication credential dialogs lockPref("security.mixed_content.block_display_content", true); // block insecure passive content lockPref("network.dns.disableIPv6", true); lockPref("network.http.referer.XOriginPolicy", 0); // default, might be worth changing to 2 to stop sending them completely lockPref("network.http.referer.XOriginTrimmingPolicy", 2); // trim referer to only send scheme, host and port lockPref("media.peerconnection.ice.no_host", true); // don't use any private IPs for ICE candidate lockPref("media.peerconnection.ice.default_address_only", true); // use a single interface for ICE candidates, the vpn one when a vpn is used lockPref("network.gio.supported-protocols", ""); // disable gio as it could bypass proxy lockPref("network.file.disable_unc_paths", true); // hidden, disable using uniform naming convention to prevent proxy bypass lockPref("network.proxy.socks_remote_dns", true); // forces dns query through the proxy when using one lockPref("media.peerconnection.ice.proxy_only_if_behind_proxy", true); // force webrtc inside proxy when one is used lockPref("network.trr.confirmationNS", "skip"); // skip undesired doh test connection lockPref("network.dns.disablePrefetch", true); // disable dns prefetching lockPref("network.trr.mode", 2); lockPref("network.trr.uri", "https://dns.quad9.net/dns-query"); lockPref("network.predictor.enabled", false); lockPref("network.prefetch-next", false); lockPref("network.http.speculative-parallel-limit", 0); lockPref("browser.places.speculativeConnect.enabled", false); lockPref("browser.urlbar.dnsResolveSingleWordsAfterSearch", 0); lockPref("browser.urlbar.speculativeConnect.enabled", false); lockPref("browser.fixup.alternate.enabled", false); lockPref("network.manage-offline-status", false); lockPref("privacy.resistFingerprinting", true); lockPref("privacy.resistFingerprinting.block_mozAddonManager", true); // prevents rfp from breaking AMO and goes on but to long for posting

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With the code you posted that settings locked for me, so there might be an error in your file that possibly throws an exception. You can check the Browser Console for possible errors.

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Here is the full config: https://pastebin.com/XLF4ciiv Don't know why trrmode isn't locked, how do i check for errors in the console?

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If you create a new profile and look at what preferences get changed by your file, how far does Firefox get in the list? Maybe that would help suggest a problem line.

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Does this pref (and other prefs in the file) has a lock icon at the far left on the about:config page and is it grayed ?

You aren't using GPO rules that could interfere ?

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In the cfg file: lockPref("network.trr.mode", 2); lockpref means a lock symbol should be visible in about:config but that is not the case for whatever reason. value 2 means enabled, correct?

i imported the exact same config on a new system and DoH remains unchecked even if the cfg says lockpref-2 in windows GPO i only changed 2 settings, enabled QoS to 100% bandwith instead of default 80% and max bandwidth to max.

im thinking the issue must be within the cfg file? some settings in conflict with each other, but how am i supposed to figure it out when there is so many settings.. guess it has to be a setting releated to network, DoH, dns etc?

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You can check for errors with your autoconfig.cfg file. Does it work if you only place that trr line in the autoconfig.cfg file?

// autoconfig.cfg needs to start with a comment line as the first line is skipped
lockPref("network.trr.mode", 2);

You can use the autoconfig.cfg file in the Firefox installation folder to initialize (set/lock) preferences and run privileged JavaScript code (needs sandbox disabled).

To use Autoconfig, place two files into the Firefox installation directory.

  • on Windows, they go into the same directory where Firefox is installed
  • on macOS, they go into the Contents/Resources directory of the Firefox.app

The autoconfig.js file that specifies to use autoconfig.cfg is placed into the "defaults\pref" directory where the channel-prefs.js file is located.

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

The autoconfig.cfg file is placed at the top level of the Firefox directory.

  • autoconfig.cfg and autoconfig.js need to start with a comment line (//)
  • autoconfig.js needs to use Unix line endings (LF instead of CR/LF)

See also:

Athraithe ag cor-el ar

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i placed autoconfig.js with the code // pref("general.config.filename", "autoconfig.cfg"); pref("general.config.obscure_value", 0); into prefs

then placed autoconfig.cfg into installation directory where exe is located with the code // autoconfig.cfg needs to start with a comment line as the first line is skipped lockPref("network.trr.mode", 2);

now by default DoH was active but not locked, i disabled it, restarted browser and it was still disabled even when cfg says lockpref, no idea what's going on here.

is there any difference naming the content of autoconfig.js firefox.cfg instead of autoconfig.cfg? will work the same way?

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You can use any filename for the autoconfig file as long as you ensure that the name in autoconfig.js file and the CFG file are the same filename.

You didn't confirm that the pref(s) show as locked on about:config. Do the other prefs you locked have a lock icon showing in about:config ?

Does the autoconfig.js file use Unix line endings (i.e. LF (%0a)) and not CR/LF ?

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No networktrrmode doesn't show a lock icon at about:config All other settings i checked in about:config have the lock icon

How do i check for unix code endings? i only see it ends with .js Also i am using librewolf version of firefox now, there is no need to autoconfig.js The librewolf.cfg is functional without an autoconfig.js file

DoH was working before, don't know why it doesn't anymore.. Can't see any spelling erros in the cfg.

lockPref("network.trr.mode", 2);

Full cfg = https://pastebin.com/XLF4ciiv

Athraithe ag Firefox_Beginner ar

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If all other pref lines have a lock icon then the autoconfig.cfg file should be working. If network.trr.mode is the only pref that isn't working then looks that this pref gets overwritten somehow. Only GPO rules or a policies.json file can do this.

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No idea what is wrong with librewolf, i reinstall firefox, tested the cfg there and DoH is active and locked, it works.

Athraithe ag Firefox_Beginner ar

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