Is there any such .conf file for Firefox to edit about:config?
Ubuntu – .conf page for Firefox’s about:config
configurationfirefox
Related Solutions
[This doesn't provide what you've asked for but is a different way to achieve the same result.]
First, about the warning... You can make sure you never see it again (on a per profile basis) as shown below:
Now, as regards the preferences you desire. In general, you can create a simple text file called user.js. This file has to be placed in the relevant profile folder such as /home/username/.mozilla/firefox/random.default (where random is something unique to each user).
The structure and syntax of user.js is described in User.js file for example.
So in your case, you would have a line such as:
user_pref("set browser.urlbar.trimURLs","false");
or, to use your other example (but see further down):
user_pref("browser.search.defaulturl","https://duckduckgo.com/");
However, I suggest that you first ensure that the preferences you set are valid for the browser version you're using. I say this because I don't see browser.search.defaulturl at all in my about:config. I'm using Firefox 22 beta. Instead, I see:
browser.search.defaultenginename;Google
So, taking the example of using Bing instead of Google, the other line in your user.js if you're using Firefox 22, would be:
user_pref("browser.search.defaultenginename","Bing");
As the image indicates, you can search for additional engines.
So, in short, you can put your preferences in user.js and you can remove the nag screen by unticking in the first image.
Also, as indicated in the resource I linked to, you must restart the browser for the code in user.js to take effect.
Please read the update at the end of this answer regarding changes in Firefox 52.
Acording to the Firefox developer documentation plugins live here:
- Directory pointed to by
MOZ_PLUGIN_PATHenvironment variable ~/.mozilla/plugins/usr/lib/mozilla/plugins(on non-Ubuntu 64-bit systems,/usr/lib64/mozilla/pluginsmight be used instead)- Plug-ins within toolkit bundles
[Profile directory]/plugins, where[Profile directory]is a user profile directory
Update for Firefox >=52
As of Firefox 52 support for NPAPI plugins has been dropped. All plugins living in one of the above directories are ignored, with the exception of Adobe Flash.
If you installed Flash with the flashplugin-installer package, it's loaded through a symlink in /usr/lib/mozilla/plugins that ultimately links to /usr/lib/flashplugin-installer/libflashplayer.so.
Best Answer
As Rinzwind already pointed out, the
prefs.jsfile is what changes when you useabout:config. It actually is a javascript file though, but it mostly just calls theuser_pref()function many times (for me it’s over 100).If you’re looking to make changes to Firefox configuration though it generally works better to create a
user.jsfile in the same location asprefs.js. On startup, Firefox first runsprefs.jsto load those settings, then runsuser.js. Once you exit, the settings fromuser.jsare also saved inprefs.js. Firefox doesn’t write touser.jsso you won’t lose your settings, and it’ll be easy to manage just a few lines of settings there instead of being mixed in with everything else inprefs.js.